# Missouri's 4th District margin of victory

Missouri's 4th District

Updated: September 4, 2026

Category: Elections

Tags: US Elections

HTML: /markets/elections/us-elections/missouri-s-4th-district-margin-of-victory/

## Short Answer

**Republicans are expected to win Missouri's 4th District by at least 14 points, supported by Decision Desk HQ's R+14 forecast for incumbent Mark Alford, his significant fundraising advantage, and the district's R+44.7 margin in 2024.** The **market** prices this outcome at **79%**.

## Key Claims (September 2026)

**- - Republicans winning by 14+ points is favored, aligning with Decision Desk HQ's forecast.** - Alford's substantial financial advantage and 2024 R+44.7 district margin suggest higher outcomes.
- Non-partisan analyses consistently rate the district strongly Republican, supporting wide margins.

## Market Behavior & Drivers

Incumbent Mark Alford's significant financial advantage and the district's R+44.7 margin in 2024 reinforce higher margin expectations, with the **market** at **70%**.

The primary price move in this market, a spike from 1.0% to 70.0% around September 3, 2026, was not driven by a specific news catalyst. The provided context finds no reported development coinciding with the repricing. The move appears to be a market correction based on fundamental data rather than a reaction to a new event.

The district's baseline political metrics support a high Republican margin of victory. Missouri's 4th District has a Cook Partisan Voter Index of R+21. Furthermore, the incumbent Republican, Mark Alford, secured a 44.7 percentage point victory in the 2024 general election. The market's shift to 70.0% aligns the contract price with these established fundamentals. The initial 1.0% price was set on zero trading volume, indicating it did not represent a market consensus before the correction.

### Who Wins and Why

| Outcome | Market | Model | Why |
| --- | --- | --- | --- |
| Republicans, 20+ pts | 70.0% | 66.0% | Historical district performance (R+44.7 in 2024) and incumbent's fundraising advantage suggest a higher margin. |
| Republicans, 14+ pts | 79.0% | 73.5% | Decision Desk HQ forecasts an R+14 margin for the incumbent in this Republican-leaning district. |
| Republicans, 11+ pts | 59.0% | 76.5% | Decision Desk HQ forecasts an R+14 margin for the favored incumbent in this Republican-leaning district. |

## Model vs Market

| Outcome | Market Probability | Octagon Model Probability |
| --- | --- | --- |
| Republicans, 20+ pts | 70.0% | 66.0% |
| Republicans, 14+ pts | 79.0% | 73.5% |
| Republicans, 11+ pts | 59.0% | 76.5% |
| Republicans, 26+ pts | 45.0% | 38.0% |
| Republicans, 29+ pts | 11.0% | 9.9% |
| Republicans, 17+ pts | 41.0% | 68.0% |
| Republicans, 23+ pts | 24.0% | 40.0% |
| Republicans, 5+ pts | 78.0% | 82.0% |
| Republicans, 8+ pts | 0.0% | 79.5% |

- Expiration: November 3, 2027

## Significant Price Movements

#### 📈 September 03, 2026: 69.0pp spike

Price increased from 1.0% to 70.0%

**Outcome:** Republicans, 20+ pts

**What happened:** There is no evidence of a 69.0 percentage point spike occurring on September 3, 2026, in the prediction market for Missouri's 4th District general election margin of victory [[^]](https://robinhood.com/us/en/prediction-markets/elections/events/missouris-4th-district-margin-of-victory-nov-03-2026/). The general election for this district is scheduled for November 3, 2026, thus a final margin of victory does not yet exist [[^]](https://robinhood.com/us/en/prediction-markets/elections/events/missouris-4th-district-margin-of-victory-nov-03-2026/). While incumbent Republican Mark Alford secured a primary victory on August 4, 2026, with approximately 77.7% of the vote [[^]](https://www.nytimes.com/interactive/2026/08/04/us/elections/results-missouri-us-house-4-primary.html), this distinct event does not correspond to the described general election market movement. Consequently, social media cannot be identified as a primary driver, as the stated market movement itself is not substantiated by the provided research.

## Contract Snapshot

For a "YES" resolution, the Republican candidate must win Missouri's 4th District election by a margin equal to or greater than the specific percentage point threshold defined by the contract. A "NO" resolution occurs if the Republican candidate wins by a margin less than that threshold, or does not win the election. Trading for this market begins on November 3, 8:00 AM EST, and the maximum payout date is listed as November 3, 2027. No special settlement conditions are explicitly detailed in the provided content.

## Market Discussion

As of September 4, 2026, incumbent Republican Mark Alford is a heavy favorite against Democratic challenger Jordan Herrera in Missouri's 4th Congressional District, with prediction markets showing his win probability between 92% and 96% [[^]](https://robinhood.com/us/en/prediction-markets/elections/events/mo-04-house-winner-nov-03-2026/)[[^]](https://www.lines.com/prediction-markets/elections/mo-04-house-election-winner)[[^]](https://votes.decisiondeskhq.com/races/2026-11-03/missouri-us-house-4-general-election/markets)[[^]](https://polymarket.copilot.markets/event/mo-04-house-election-winner)[[^]](https://www.worldeventtrading.com/predictions/mo-04-house-election-winner-odds-2026-11-03)[[^]](https://votes.decisiondeskhq.com/races/2026-11-03/missouri-us-house-4-general-election/forecast)[[^]](https://integration-votes.decisiondeskhq.com/races/2026-11-03/missouri-us-house-4-general-election/forecast)[[^]](https://ballotpedia.org/Missouri%27s_4th_Congressional_District_election,_2026_(August_4_Democratic_primary)). Decision Desk HQ forecasts a Republican victory with a projected margin of R+14 [[^]](https://votes.decisiondeskhq.com/races/2026-11-03/missouri-us-house-4-general-election/forecast)[[^]](https://integration-votes.decisiondeskhq.com/races/2026-11-03/missouri-us-house-4-general-election/forecast)[[^]](https://integration-votes.decisiondeskhq.com/races/2026-11-03/missouri-us-house-4-general-election/markets)[[^]](https://votes.decisiondeskhq.com/races/2026-11-03/missouri-us-house-4-general-election/markets), despite mid-decade redistricting having reduced the Republican advantage in the district from roughly 23 points to approximately 10 points [[^]](https://votes.decisiondeskhq.com/races/2026-11-03/missouri-us-house-4-general-election/forecast)[[^]](https://www.pollsmax.com/2026-us-house/missouri-4/forecast/)[[^]](https://www.kcur.org/politics-elections-and-government/2026-08-05/missouri-u-s-rep-mark-alford-secures-4th-district-primary-victory-with-trumps-support-jordan-herrera).

## Market Data

| Contract | Yes Bid | Yes Ask | Last Price | Volume | Open Interest |
| --- | --- | --- | --- | --- | --- |
| Republicans, 11+ pts | 0% | 83% | 59% | $441.17 | $436.17 |
| Republicans, 14+ pts | 0% | 83% | 79% | $644 | $644 |
| Republicans, 17+ pts | 0% | 83% | 41% | $100 | $100 |
| Republicans, 20+ pts | 0% | 83% | 70% | $3,017.33 | $2,688.33 |
| Republicans, 23+ pts | 0% | 83% | 24% | $100 | $100 |
| Republicans, 26+ pts | 0% | 83% | 45% | $247.25 | $142.25 |
| Republicans, 29+ pts | 0% | 83% | 11% | $204 | $204 |
| Republicans, 5+ pts | 0% | 100% | 78% | $40.93 | $30.93 |
| Republicans, 8+ pts | 0% | 100% | 0% | $0 | $0 |

## How did the Missouri Supreme Court's September 2026 ruling on congressional maps affect the forecasted margin for Mark Alford?

Election Date MO-04 | November 3, 2026 [[^]](https://www.kctv5.com/2026/08/05/incumbent-rep-mark-alford-wins-gop-primary-missouris-4th-congressional-district/)[[^]](https://ballotpedia.org/Mark_Alford) |
Alford Win Probability | 96% [[^]](https://votes.decisiondeskhq.com/races/2026-11-03/missouri-us-house-4-general-election/forecast)[[^]](https://integration-votes.decisiondeskhq.com/races/2026-11-03/missouri-us-house-4-general-election/forecast) |
Alford Projected Margin | R+14 [[^]](https://votes.decisiondeskhq.com/races/2026-11-03/missouri-us-house-4-general-election/forecast)[[^]](https://integration-votes.decisiondeskhq.com/races/2026-11-03/missouri-us-house-4-general-election/forecast) |

**No September 2026 Missouri Supreme Court ruling impacted Mark Alford's forecast**

No September 2026 Missouri Supreme Court ruling impacted Mark Alford's forecast. Contrary to certain reports, the Missouri Supreme Court did not issue a ruling on congressional maps in September 2026, nor was there a specific judgment during that month that influenced Mark Alford's projected margin [[^]](https://ballotpedia.org/Missouri_Congressional_Map_Referendum_(2026))[[^]](https://news.ballotpedia.org/2025/12/11/referendum-to-repeal-missouris-new-congressional-map-submits-signatures-for-2026-ballot/)[[^]](https://www.ap.org/news-highlights/elections/2026/redistricting-is-rampant-ahead-of-the-us-house-midterm-elections-what-states-are-taking-action/). The court's most recent significant decision on redistricting took place on May 12, 2026. This ruling established that House Bill 1, the congressional redistricting law, was not automatically suspended by the submission of referendum signatures. Consequently, the congressional map enacted by Governor Kehoe remained valid for the 2026 elections [[^]](https://ballotpedia.org/Missouri_Congressional_Map_Referendum_(2026))[[^]](https://news.ballotpedia.org/2025/12/11/referendum-to-repeal-missouris-new-congressional-map-submits-signatures-for-2026-ballot/)[[^]](https://www.ap.org/news-highlights/elections/2026/redistricting-is-rampant-ahead-of-the-us-house-midterm-elections-what-states-are-taking-action/).

Mark Alford is heavily favored to win reelection in Missouri's 4th District. Incumbent Republican Mark Alford is seeking reelection in Missouri's 4th Congressional District in the general election on November 3, 2026 [[^]](https://www.kctv5.com/2026/08/05/incumbent-rep-mark-alford-wins-gop-primary-missouris-4th-congressional-district/)[[^]](https://ballotpedia.org/Mark_Alford). As of early September 2026, Alford is projected to win with a **96%** **probability**, holding a projected margin of victory of R+14 [[^]](https://votes.decisiondeskhq.com/races/2026-11-03/missouri-us-house-4-general-election/forecast)[[^]](https://integration-votes.decisiondeskhq.com/races/2026-11-03/missouri-us-house-4-general-election/forecast). The legal challenges concerning the 2025 redistricting map did not significantly alter this partisan forecast, and Alford continues to be a strong favorite in the 4th District [[^]](https://www.pollsmax.com/2026-us-house/missouri-4/forecast/)[[^]](https://www.270towin.com/2026-house-election/states/missouri).

## What do historical election results in Missouri's 4th District under the current 2022 map suggest for a likely 2026 margin?

2026 Forecasted Margin | R+14 (Decision Desk HQ) [[^]](https://votes.decisiondeskhq.com/races/2026-11-03/missouri-us-house-4-general-election/forecast)[[^]](https://integration-votes.decisiondeskhq.com/races/2026-11-03/missouri-us-house-4-general-election/forecast) |
Cook PVI Rating | R+23 [[^]](https://ballotpedia.org/Missouri%27s_4th_Congressional_District)[[^]](https://www.pollsmax.com/2026-us-house/missouri-4/forecast/) |
2024 General Election Margin | R+44.7% (Mark Alford) [[^]](https://www.nytimes.com/interactive/2024/11/05/us/elections/results-missouri-us-house-4.html)[[^]](https://www.washingtonpost.com/elections/results/2024/11/05/missouri-house-district-4/) |

**Prediction markets and analysts project a strong Republican lead for 2026**

Prediction markets and analysts project a strong Republican lead for 2026. As of early September 2026, prediction markets indicate a Republican victory margin of 11 percentage points or more in the Missouri 4th District U.S. House election [[^]](https://www.predictionedge.com/elections/us-house/missouri-district-4-race-winner-by-party/)[[^]](https://robinhood.com/us/en/prediction-markets/elections/events/missouris-4th-district-margin-of-victory-nov-03-2026/). This outlook is reinforced by Decision Desk HQ, which forecasts a Republican margin of R+14 for the district [[^]](https://votes.decisiondeskhq.com/races/2026-11-03/missouri-us-house-4-general-election/forecast)[[^]](https://integration-votes.decisiondeskhq.com/races/2026-11-03/missouri-us-house-4-general-election/forecast). Such projections align with the district's established partisan lean, reflected in its Cook Partisan Voter Index (PVI) rating of R+23, a metric consistently observed across recent election cycles [[^]](https://ballotpedia.org/Missouri%27s_4th_Congressional_District)[[^]](https://www.pollsmax.com/2026-us-house/missouri-4/forecast/)[[^]](https://ballotpedia.org/United_States_House_of_Representatives_elections_in_Missouri,_2024)[[^]](https://ballotpedia.org/Missouri%27s_4th_Congressional_District_election,_2024_(August_6_Democratic_primary)).

Historical election results confirm the district's consistent Republican preference. In the August 2026 primary elections, incumbent Republican Mark Alford secured the GOP nomination with **72.1%** of the vote, while Jordan Herrera won the Democratic nomination with **30.9%** [[^]](https://www.nbcnews.com/politics/2026-primary-elections/missouri-us-house-district-4-results). Further underscoring this trend, the 2024 general election saw Mark Alford achieve a significant victory, winning by 44.7 percentage points with **71.1%** of the vote against Democrat Jeanette Cass [[^]](https://www.nytimes.com/interactive/2024/11/05/us/elections/results-missouri-us-house-4.html)[[^]](https://www.washingtonpost.com/elections/results/2024/11/05/missouri-house-district-4/). Within the current district boundaries, the 2020 presidential election also demonstrated a substantial Republican advantage, with **68.7%** of votes cast for the Republican candidate compared to **29.3%** for the Democratic candidate [[^]](https://ballotpedia.org/Missouri%27s_4th_Congressional_District_election,_2022)[[^]](https://ballotpedia.org/Missouri%27s_4th_Congressional_District_election,_2024_(August_6_Democratic_primary)).

## How do the 2026 campaign fundraising totals and cash-on-hand compare between Mark Alford and Jordan Herrera?

Alford Fundraising | $1,392,968 (as of July 15, 2026) [[^]](https://ballotpedia.org/Missouri%27s_4th_Congressional_District_election,_2026)[[^]](https://www.fec.gov/data/candidate/H2MO04207/) |
Herrera Fundraising | $41,657 (as of July 15, 2026) [[^]](https://ballotpedia.org/Missouri%27s_4th_Congressional_District_election,_2026)[[^]](https://www.fec.gov/data/candidate/H6MO05254/) |
Alford Win Probability | 96% (Decision Desk HQ) [[^]](https://votes.decisiondeskhq.com/races/2026-11-03/missouri-us-house-4-general-election/forecast)[[^]](https://integration-votes.decisiondeskhq.com/races/2026-11-03/missouri-us-house-4-general-election/forecast) |

**Incumbent Mark Alford significantly outpaced Jordan Herrera in campaign finances**

Incumbent Mark Alford significantly outpaced Jordan Herrera in campaign finances.
As of July 15, 2026, Republican incumbent Mark Alford reported substantially higher campaign fundraising totals and cash-on-hand compared to Democratic candidate Jordan Herrera [[^]](https://ballotpedia.org/Missouri%27s_4th_Congressional_District_election,_2026)[[^]](https://www.fec.gov/data/candidate/H2MO04207/)[[^]](https://www.fec.gov/data/candidate/H6MO05254/). For this reporting period, Alford raised **$1,392,968** and maintained **$747,401** in cash-on-hand [[^]](https://ballotpedia.org/Missouri%27s_4th_Congressional_District_election,_2026)[[^]](https://www.fec.gov/data/candidate/H2MO04207/). In contrast, Herrera reported raising **$41,657** with **$19,366** in cash-on-hand during the same period [[^]](https://ballotpedia.org/Missouri%27s_4th_Congressional_District_election,_2026)[[^]](https://www.fec.gov/data/candidate/H6MO05254/).

Forecasts overwhelmingly predict a Republican victory in Missouri's 4th District.
This significant financial disparity aligns with a strong consensus across prediction markets and electoral forecasts for a Republican victory in Missouri's 4th Congressional District [[^]](https://robinhood.com/us/en/prediction-markets/elections/events/missouris-4th-district-margin-of-victory-nov-03-2026/)[[^]](https://polymarket.com/event/mo-04-house-election-winner)[[^]](https://www.270towin.com/2026-house-election/states/missouri)[[^]](https://votes.decisiondeskhq.com/races/2026-11-03/missouri-us-house-4-general-election/forecast)[[^]](https://integration-votes.decisiondeskhq.com/races/2026-11-03/missouri-us-house-4-general-election/forecast). Decision Desk HQ predicts Mark Alford is "safe to win," assigning a **96%** win **probability** and a projected R+14 margin [[^]](https://votes.decisiondeskhq.com/races/2026-11-03/missouri-us-house-4-general-election/forecast)[[^]](https://integration-votes.decisiondeskhq.com/races/2026-11-03/missouri-us-house-4-general-election/forecast). Similarly, prediction markets indicate a **94%** **probability** for a Republican to retain the seat [[^]](https://robinhood.com/us/en/prediction-markets/elections/events/missouris-4th-district-margin-of-victory-nov-03-2026/)[[^]](https://polymarket.com/event/mo-04-house-election-winner)[[^]](https://www.270towin.com/2026-house-election/states/missouri).

## Is there any public polling data available for the 2026 Mark Alford vs. Jordan Herrera matchup in Missouri's 4th District?

Public Polling Data Status | Not available as of September 4, 2026 [[^]](https://www.kcur.org/politics-elections-and-government/2026-08-05/missouri-u-s-rep-mark-alford-secures-4th-district-primary-victory-with-trumps-support-jordan-herrera)[[^]](https://robinhood.com/us/en/prediction-markets/elections/events/missouris-4th-district-margin-of-victory-nov-03-2026/)[[^]](https://www.270towin.com/2026-house-election/states/missouri)[[^]](https://ballotpedia.org/Missouri%27s_4th_Congressional_District_election,_2026)[[^]](https://votes.decisiondeskhq.com/races/2026-11-03/missouri-us-house-4-general-election/forecast)[[^]](https://votes.decisiondeskhq.com/races/2026-11-03/missouri-us-house-4-general-election)[[^]](https://ballotpedia.org/United_States_House_of_Representatives_elections_in_Missouri,_2026) |
Cook Partisan Voting Index (PVI) | R+10 [[^]](https://www.kcur.org/politics-elections-and-government/2026-08-05/missouri-u-s-rep-mark-alford-secures-4th-district-primary-victory-with-trumps-support-jordan-herrera) |
Decision Desk HQ Forecast | Mark Alford to win with 96% probability, R+14 margin [[^]](https://votes.decisiondeskhq.com/races/2026-11-03/missouri-us-house-4-general-election/forecast)[[^]](https://integration-votes.decisiondeskhq.com/races/2026-11-03/missouri-us-house-4-general-election/forecast) |

**No public polling data exists for the 2026 MO-04 general election**

No public polling data exists for the 2026 MO-04 general election. As of September 4, 2026, no public polling data is available for the general election matchup in Missouri's 4th Congressional District between Republican incumbent Mark Alford and Democratic challenger Jordan Herrera [[^]](https://www.kcur.org/politics-elections-and-government/2026-08-05/missouri-u-s-rep-mark-alford-secures-4th-district-primary-victory-with-trumps-support-jordan-herrera)[[^]](https://robinhood.com/us/en/prediction-markets/elections/events/missouris-4th-district-margin-of-victory-nov-03-2026/)[[^]](https://www.270towin.com/2026-house-election/states/missouri)[[^]](https://ballotpedia.org/Missouri%27s_4th_Congressional_District_election,_2026)[[^]](https://votes.decisiondeskhq.com/races/2026-11-03/missouri-us-house-4-general-election/forecast)[[^]](https://votes.decisiondeskhq.com/races/2026-11-03/missouri-us-house-4-general-election)[[^]](https://ballotpedia.org/United_States_House_of_Representatives_elections_in_Missouri,_2026). Both candidates secured their respective party nominations in August 2026, officially setting the stage for the general election contest [[^]](https://www.kcur.org/politics-elections-and-government/2026-08-05/missouri-u-s-rep-mark-alford-secures-4th-district-primary-victory-with-trumps-support-jordan-herrera)[[^]](https://www.kctv5.com/2026/08/05/incumbent-rep-mark-alford-wins-gop-primary-missouris-4th-congressional-district/)[[^]](https://www.kshb.com/news/local-news/rep-alford-cruises-to-missouri-primary-victory-will-face-herrera-in-november).

The district is considered strongly Republican despite redistricting changes. Despite the absence of specific polling, Missouri's 4th Congressional District is widely considered strongly Republican [[^]](https://www.kcur.org/politics-elections-and-government/2026-08-05/missouri-u-s-rep-mark-alford-secures-4th-district-primary-victory-with-trumps-support-jordan-herrera)[[^]](https://robinhood.com/us/en/prediction-markets/elections/events/missouris-4th-district-margin-of-victory-nov-03-2026/)[[^]](https://www.270towin.com/2026-house-election/states/missouri). Redistricting has influenced the district's competitiveness, shifting its Cook Partisan Voting Index from an R+23 lean to an R+10 lean [[^]](https://www.kcur.org/politics-elections-and-government/2026-08-05/missouri-u-s-rep-mark-alford-secures-4th-district-primary-victory-with-trumps-support-jordan-herrera). Election forecasting sites track the expected outcome; for instance, Decision Desk HQ projects Mark Alford to win with a **96%** **probability** and a projected margin of R+14 as of September 1, 2026 [[^]](https://votes.decisiondeskhq.com/races/2026-11-03/missouri-us-house-4-general-election/forecast)[[^]](https://integration-votes.decisiondeskhq.com/races/2026-11-03/missouri-us-house-4-general-election/forecast).

## How do election forecasts from major non-partisan outlets like Decision Desk HQ and the Cook Political Report rate the MO-04 race?

District Classification | Solid/Safe Republican (Cook Political Report, Decision Desk HQ, Inside Elections) [[^]](https://ballotpedia.org/Missouri%27s_4th_Congressional_District_election,_2026)[[^]](https://ballotpedia.org/Missouri%27s_4th_Congressional_District_election,_2026_(August_4_Democratic_primary)) |
Projected Margin | R+14 (Decision Desk HQ) [[^]](https://votes.decisiondeskhq.com/races/2026-11-03/missouri-us-house-4-general-election/forecast)[[^]](https://integration-votes.decisiondeskhq.com/races/2026-11-03/missouri-us-house-4-general-election/forecast) |
Cook Partisan Voter Index (CPVI) | R+21, 27th most Republican nationally [[^]](https://ballotpedia.org/Missouri%27s_4th_Congressional_District_election,_2026_(August_4_Republican_primary)) |

**Non-partisan analyses consistently rate MO-04 as strongly Republican**

Non-partisan analyses consistently rate MO-04 as strongly Republican. Major non-partisan political outlets widely classify Missouri's 4th Congressional District (MO-04) as either Solid Republican or Safe Republican for the 2026 general election [[^]](https://ballotpedia.org/Missouri%27s_4th_Congressional_District_election,_2026)[[^]](https://ballotpedia.org/Missouri%27s_4th_Congressional_District_election,_2026_(August_4_Democratic_primary)). This consensus includes assessments from organizations such as the Cook Political Report, Decision Desk HQ, and Inside Elections [[^]](https://ballotpedia.org/Missouri%27s_4th_Congressional_District_election,_2026)[[^]](https://ballotpedia.org/Missouri%27s_4th_Congressional_District_election,_2026_(August_4_Democratic_primary)). The district's strong Republican lean is further highlighted by its Cook Partisan Voter Index (CPVI) of R+21, which places it as the 27th most Republican district nationwide [[^]](https://ballotpedia.org/Missouri%27s_4th_Congressional_District_election,_2026_(August_4_Republican_primary)).

Forecasts indicate a very high **probability** of a Republican victory. Specific projections for the 2026 race show incumbent Mark Alford with a **96%** chance of winning, according to Decision Desk HQ, which also forecasts a projected margin of R+14 [[^]](https://votes.decisiondeskhq.com/races/2026-11-03/missouri-us-house-4-general-election/forecast)[[^]](https://integration-votes.decisiondeskhq.com/races/2026-11-03/missouri-us-house-4-general-election/forecast). Complementing these projections, prediction markets actively show trading that favors a substantial Republican victory, with **market** valuations indicating **confidence** in margins exceeding 11 percentage points [[^]](https://robinhood.com/us/en/prediction-markets/elections/events/missouris-4th-district-margin-of-victory-nov-03-2026/). Incumbent Republican Mark Alford secured his position for the general election by winning the primary election on September 1, 2026 [[^]](https://www.nbcnews.com/politics/2026-primary-elections/missouri-us-house-district-4-results).

## What Could Change the Odds

**Catalysts for U.S.** House control prediction markets include generic-ballot polling, presidential approval ratings, economic data releases, redistricting litigation, candidate-level developments, and turnout reports [[^]](https://cryptoslate.com/predictions/**market**/which-party-will-win-the-house-in-2026/)[[^]](https://predictiongenius.io/markets/which-party-will-u-s-house)[[^]](https://www.electionodds.com/house/)[[^]](https://www.lines.com/prediction-markets/elections/which-party-will-win-the-house-in-2026)[[^]](https://www.stokastic.com/articles/prediction-markets/house-control-odds). Breaking news events can influence voter sentiment before traditional polling reflects changes, acting as bullish or bearish catalysts [[^]](https://www.decisiondeskhq.com/press/decision-desk-hq-releases-2026-congressional-forecast-**model**)[[^]](https://news.ballotpedia.org/2026/07/31/prediction-markets-approach-200-million-in-settled-contracts-2/). Decision Desk HQ's forecast **model** for the 2026 U.S. midterm elections integrates data from prediction markets to assess race competitiveness and Congressional control, noting these markets provide signals on breaking news impacts [[^]](https://www.decisiondeskhq.com/press/decision-desk-hq-releases-2026-congressional-forecast-**model**)[[^]](https://integration-votes.decisiondeskhq.com/forecast/2026).

**In Missouri's 4th Congressional District, incumbent Republican Mark Alford secured the August 4, 2026, primary victory with 77.7% of the vote and will face Democratic challenger Jordan Herrera in the November 3, 2026, general election [[^]](https://www.kcur.org/politics-elections-and-government/2026-08-05/missouri-u-s-rep-mark-alford-secures-4th-district-primary-victory-with-trumps-support-jordan-herrera)[[^]](https://www.kshb.com/news/local-news/rep-alford-cruises-to-missouri-primary-victory-will-face-herrera-in-november).** Following redistricting, the district's Cook Partisan Voting Index shifted from R+23 to R+10, now including parts of Kansas City and Jackson County [[^]](https://www.kcur.org/politics-elections-and-government/2026-08-05/missouri-u-s-rep-mark-alford-secures-4th-district-primary-victory-with-trumps-support-jordan-herrera). This contrasts with Alford's 44.66 percentage point margin of victory in the 2024 U.S. House election for the same district [[^]](https://ballotpedia.org/Election_results,_2024:_Congressional_margin_of_victory_analysis).

## Key Dates & Catalysts

- **Expiration:** November 03, 2027
- **Closes:** November 03, 2027

## Decision-Flipping Events

- Catalysts for U.S.
- House control prediction markets include generic-ballot polling, presidential approval ratings, economic data releases, redistricting litigation, candidate-level developments, and turnout reports [^] [^] [^] [^] [^] .
- Breaking news events can influence voter sentiment before traditional polling reflects changes, acting as bullish or bearish catalysts [^] [^] .
- Decision Desk HQ's forecast **model** for the 2026 U.S.

## Related Research Reports

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## Historical Resolutions

**Historical Resolutions:** 6 markets in this series

**Outcomes:** 2 resolved YES, 4 resolved NO

**Recent resolutions:**

- KXMIDTERMMOV-CAGOVPSHILT-P5: NO (Jul 11, 2026)
- KXMIDTERMMOV-CAGOVPSHILT-P3: NO (Jul 11, 2026)
- KXMIDTERMMOV-CAGOVPSHILT-P1: NO (Jul 11, 2026)
- KXMIDTERMMOV-CAGOVPXBECE-P5: NO (Jul 11, 2026)
- KXMIDTERMMOV-CAGOVPXBECE-P3: YES (Jul 11, 2026)

## Disclaimer

This content is for informational and educational purposes only and does not constitute financial, investment, legal, or trading advice.
Prediction markets involve risk of loss. Past performance does not guarantee future results.
We are not affiliated with Kalshi or any prediction market platform. Market data may be delayed or incomplete.

### Data Sources & Model Transparency

**Data Sources:** Octagon Deep Research aggregates information from multiple sources including news, filings, and market data.

**Freshness:** Analysis is generated periodically and may not reflect the latest developments. Verify critical information from primary sources.

## Attribution Policy

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