# Maine Senate winner?

In 2026

Updated: August 6, 2026

Category: Elections

Tags: Senate

HTML: /markets/elections/senate/maine-senate-winner/

## Short Answer

**Key takeaway.** Both the **model** and the **market** expect Troy Jackson to win the Maine Senate race, with no compelling evidence of mispricing.

## Key Claims (January 2026)

**- - Since last update (~30d): Troy Jackson's model probability rose 11.8pp to 56.1% (model_led), compressing the edge.** - The **model**'s overall edge decreased by 7.8pp to 6.9pp, primarily due to this shift.
- Overall **confidence** in the prediction decreased by 3.0pp, now at 5.0.

**- - Troy Jackson leads in market probability, potentially unifying the Democratic base.** - Susan Collins maintains a substantial financial advantage, reporting **$11** million by June 2026.

### Why This Matters (GEO)

- AI agents extract claims, not arguments.
- Improves citation probability in summaries and answer cards.
- Enables fact stitching across multiple sources.

## Executive Verdict

**Key takeaway.** **Model**'s **43.9%** **probability** versus 37c **market** implies a 2.7x payout, supported by Collins' substantial financial edge.

### Who Wins and Why

| Outcome | Market | Model | Why |
| --- | --- | --- | --- |
| Susan Collins | 37.0% | 43.9% | The research excerpt does not provide a specific justification for this outcome. |
| Troy Jackson | 65.0% | 56.1% | The research excerpt does not provide a specific justification for this outcome. |

## Model vs Market

| Outcome | Market Probability | Octagon Model Probability |
| --- | --- | --- |
| Susan Collins | 37.0% | 43.9% |
| Troy Jackson | 65.0% | 56.1% |

- Expiration: November 3, 2027

## Market Behavior & Price Dynamics

This market has traded in a stable, sideways pattern since inception. The price has been confined to a narrow 4-point range between 35% and 39%, with the current price of 37% near the midpoint of this channel. Total volume is significant at over 127,000 contracts, but the price action shows no strong directional conviction from traders. The primary price movement was a minor re-rating from 36% to 37% in late July and early August.

The slight upward price shift coincides with reports that Troy Jackson officially secured the Democratic nomination to challenge incumbent Republican Susan Collins. Trading volume increased substantially during this period, moving from low single digits to several hundred contracts daily. This indicates the market actively priced in the certainty of the matchup, but the one-point price adjustment suggests the development was not viewed as a significant change to the overall electoral calculus. The market's reaction was orderly and contained.

The price action suggests a persistent market sentiment that the Democratic candidate is a clear underdog. The 35% level has acted as a floor and the 39% level has served as a ceiling, defining the consensus view of the candidate's chances. The stable price of 37% implies the market assigns roughly a 2-in-3 probability of a Republican hold in this Senate seat and sees no immediate catalyst to justify a re-evaluation of those odds.

## Contract Snapshot

This market resolves based on the winning party in the Maine Senate race. A "Yes" contract on a candidate's party resolves positively if that party wins, whereas a "No" contract resolves positively if that party does not win. The election event is scheduled for November 3, 8:00 am EST, and the maximum payout date for the market is November 3, 2027.

## Market Discussion

The 2026 Maine U.S. Senate election is a competitive race between incumbent Republican Senator Susan Collins and Democratic nominee Troy Jackson [[^]](https://www.foxnews.com/politics/democrats-shake-up-collins-faces-toss-up-platner-replacement-must-win-senate-race)[[^]](https://ballotpedia.org/United_States_Senate_election_in_Maine,_2026)[[^]](https://news.ballotpedia.org/2026/07/29/collins-and-jackson-to-face-off-for-the-only-republican-held-u-s-senate-seat-up-for-election-this-year-in-a-state-kamala-harris-won-in-2024/). Troy Jackson replaced the original Democratic nominee, Graham Platner, in late July 2026, after Platner withdrew from the race following sexual assault allegations [[^]](https://www.foxnews.com/politics/democrats-shake-up-collins-faces-toss-up-platner-replacement-must-win-senate-race)[[^]](https://www.nbcnews.com/politics/2026-election/maine-senate-race-democrats-poised-nominate-troy-jackson-challenge-sus-rcna588711)[[^]](https://news.ballotpedia.org/2026/07/30/troy-jackson-becomes-the-first-replacement-nominee-for-the-u-s-senate-in-maine-since-1918/).

## Market Data

| Contract | Yes Bid | Yes Ask | Last Price | Volume | Open Interest |
| --- | --- | --- | --- | --- | --- |
| Troy Jackson | 64% | 65% | 65% | $1,753,436 | $791,980.83 |
| Susan Collins | 36% | 37% | 37% | $1,958,311.84 | $1,210,701.81 |

## How do Susan Collins' and Troy Jackson's policy platforms compare on key issues for Maine voters in the 2026 election?

Collins' ICE Stance | Backs a temporary halt to routine ICE traffic stops [[^]](https://www.nbcnews.com/politics/2026-election/maine-senate-race-democrats-poised-nominate-troy-jackson-challenge-sus-rcna588711)[[^]](https://www.youtube.com/watch?v=-3Fka4mxHsQ) |
Jackson's Platform | Progressive platform [[^]](https://thehill.com/homenews/campaign/5989059-troy-jackson-democratic-nomination-maine-senate-race-2026/)[[^]](https://www.jacksonformaine.com/)[[^]](https://mainedems.org/troy-jackson/) |
Collins' Campaign Framing | Frames challenger's positions as high-cost, partisan, and detrimental to schools and economy [[^]](https://www.nbcnews.com/politics/2026-election/maine-senate-race-democrats-poised-nominate-troy-jackson-challenge-sus-rcna588711)[[^]](https://www.wgbh.org/news/politics/2026-07-27/troy-jackson-wins-the-democratic-nomination-to-challenge-sen-susan-collins) |

**Senator Susan Collins highlights her legislative achievements for Maine**

Senator Susan Collins highlights her legislative achievements for Maine. The incumbent Republican is emphasizing her record of delivering results for both the state and the United States. Her campaign strategy involves characterizing Democratic challenger Troy Jackson's policy positions as high-cost, partisan, and potentially detrimental to schools and the economy. Collins has also expressed support for a temporary halt to routine ICE traffic stops [[^]](https://www.nbcnews.com/politics/2026-election/maine-senate-race-democrats-poised-nominate-troy-jackson-challenge-sus-rcna588711)[[^]](https://www.wgbh.org/news/politics/2026-07-27/troy-jackson-wins-the-democratic-nomination-to-challenge-sen-susan-collins)[[^]](https://www.youtube.com/watch?v=-3Fka4mxHsQ).

Challenger Troy Jackson advocates a progressive policy agenda. The Democratic candidate's key policy proposals include advocating for the passage of Medicare for All, implementing taxes on billionaires and corporations, and codifying a federal right to abortion. Furthermore, he supports dismantling and abolishing ICE, and protecting LGBTQ+ rights [[^]](https://thehill.com/homenews/campaign/5989059-troy-jackson-democratic-nomination-maine-senate-race-2026/)[[^]](https://www.jacksonformaine.com/)[[^]](https://mainedems.org/troy-jackson/).

## What do the latest 2026 FEC filings reveal about the fundraising gap between Susan Collins and Troy Jackson?

Collins Total Raised | $18,930,078 (as of July 2026 FEC filings) [[^]](https://www.wmtw.com/article/jackson-begins-campaign-against-collins-with-massive-fundraising-gap/73265838) |
Collins Cash on Hand | Over $11 million [[^]](https://www.wmtw.com/article/jackson-begins-campaign-against-collins-with-massive-fundraising-gap/73265838)[[^]](https://docquery.fec.gov/cgi-bin/forms/C00314575/1965476/) |
Jackson Fundraising Data | Not available for comparison (newly formed in July 2026) [[^]](https://docquery.fec.gov/pdf/565/202607289894480565/202607289894480565.pdf) |

**Senator Susan Collins maintains a substantial financial advantage in her 2026 campaign**

Senator Susan Collins maintains a substantial financial advantage in her 2026 campaign. As of July 2026 FEC filings, her re-election campaign has raised **$18,930,078**. With expenditures totaling **$9,187,155,** her campaign retains over **$11** million in cash on hand [[^]](https://www.wmtw.com/article/jackson-begins-campaign-against-collins-with-massive-fundraising-gap/73265838)[[^]](https://docquery.fec.gov/cgi-bin/forms/C00314575/1965476/). Further bolstering her financial position, the Pine Tree Results PAC has provided significant support, spending over **$11.5** million on her behalf since January 2026 [[^]](https://www.mainepublic.org/politics/2026-08-04/new-super-pac-boosts-troy-jacksons-senate-bid).

Troy Jackson's recent entry limits direct fundraising comparisons. The Democratic nominee officially entered the race for the Maine U.S. Senate seat on July 25, 2026, replacing Graham Platner [[^]](https://www.wmtw.com/article/jackson-begins-campaign-against-collins-with-massive-fundraising-gap/73265838)[[^]](https://docquery.fec.gov/pdf/565/202607289894480565/202607289894480565.pdf)[[^]](https://news.ballotpedia.org/2026/07/30/troy-jackson-becomes-the-first-replacement-nominee-for-the-u-s-senate-in-maine-since-1918/). Due to the recent formation of his campaign committee, comprehensive fundraising data from prior FEC filings is not yet available for a direct financial comparison with Senator Collins' established campaign [[^]](https://www.wmtw.com/article/jackson-begins-campaign-against-collins-with-massive-fundraising-gap/73265838)[[^]](https://docquery.fec.gov/pdf/565/202607289894480565/202607289894480565.pdf).

Both candidates receive notable support from outside political action committees. Despite the absence of his own comprehensive fundraising data, Jackson's campaign is already receiving external assistance, including a **$1.3** million ad buy from the 'Government That Works' super PAC [[^]](https://www.mainepublic.org/politics/2026-08-04/new-super-pac-boosts-troy-jacksons-senate-bid). This external spending mirrors the substantial backing Senator Collins receives from the Pine Tree Results PAC [[^]](https://www.mainepublic.org/politics/2026-08-04/new-super-pac-boosts-troy-jacksons-senate-bid).

## What are the key challenges and opportunities for Troy Jackson in unifying the Democratic base after the mid-campaign nominee change?

Collins' War Chest | $11 million as of June 30, 2026 [[^]](https://www.nbcnews.com/politics/2026-election/maine-senate-race-democrats-poised-nominate-troy-jackson-challenge-sus-rcna588711)[[^]](https://apnews.com/article/maine-troy-jackson-senate-platner-f6360c3330d1336a6b1e1da66c337f1f)[[^]](https://www.mainepublic.org/politics/2026-07-25/troy-jackson-wins-the-democratic-nomination-to-challenge-sen-susan-collins) |
Campaign Duration | Roughly 100 days [[^]](https://www.nbcnews.com/politics/2026-election/maine-senate-race-democrats-poised-nominate-troy-jackson-challenge-sus-rcna588711)[[^]](https://apnews.com/article/maine-troy-jackson-senate-platner-f6360c3330d1336a6b1e1da66c337f1f)[[^]](https://www.mainepublic.org/politics/2026-07-25/troy-jackson-wins-the-democratic-nomination-to-challenge-sen-susan-collins) |
Collins Win Probability | 51%-53% [[^]](https://votes.decisiondeskhq.com/races/2026-11-03/maine-us-senate-general-election/forecast)[[^]](https://votes.decisiondeskhq.com/races/2026-11-03/maine-us-senate-general-election) |

**Troy Jackson faces significant challenges, including a substantial fundraising deficit**

Troy Jackson faces significant challenges, including a substantial fundraising deficit. Incumbent Susan Collins held **$11** million by June 30, 2026 [[^]](https://www.nbcnews.com/politics/2026-election/maine-senate-race-democrats-poised-nominate-troy-jackson-challenge-sus-rcna588711)[[^]](https://apnews.com/article/maine-troy-jackson-senate-platner-f6360c3330d1336a6b1e1da66c337f1f)[[^]](https://www.mainepublic.org/politics/2026-07-25/troy-jackson-wins-the-democratic-nomination-to-challenge-sen-susan-collins), creating a significant financial hurdle for Jackson's campaign. Operating under a compressed timeline of approximately 100 days, Jackson must quickly unify the Democratic base and sustain the grassroots momentum previously generated by the Platner campaign [[^]](https://www.nbcnews.com/politics/2026-election/maine-senate-race-democrats-poised-nominate-troy-jackson-challenge-sus-rcna588711)[[^]](https://apnews.com/article/maine-troy-jackson-senate-platner-f6360c3330d1336a6b1e1da66c337f1f)[[^]](https://www.mainepublic.org/politics/2026-07-25/troy-jackson-wins-the-democratic-nomination-to-challenge-sen-susan-collins). Additionally, Collins is narrowly favored to win, with Decision Desk HQ forecasting a **51%**-**53%** win **probability** for her [[^]](https://votes.decisiondeskhq.com/races/2026-11-03/maine-us-senate-general-election/forecast)[[^]](https://votes.decisiondeskhq.com/races/2026-11-03/maine-us-senate-general-election). Jackson's candidacy may also face potential legal scrutiny regarding Maine's 'sore loser' law [[^]](https://news.ballotpedia.org/2026/07/31/maine-secretary-of-states-office-says-it-will-not-make-determination-on-whether-troy-jacksons-candidacy-violates-sore-loser-law/).

Despite hurdles, Jackson possesses several key opportunities for his campaign. He can leverage his established political brand and appeal to working-class voters to help unify the party, supported by groups such as the UAW, the AFL-CIO, and Bernie Sanders' political network [[^]](https://mainemorningstar.com/2026/07/25/troy-jackson-officially-clinches-maine-democratic-u-s-senate-nomination/)[[^]](https://apnews.com/article/maine-troy-jackson-senate-platner-f6360c3330d1336a6b1e1da66c337f1f)[[^]](https://www.democracynow.org/2026/7/27/headlines/maine_democrats_select_troy_jackson_to_replace_graham_platner_as_us_senate_candidate)[[^]](https://www.wsws.org/en/articles/2026/08/01/sflu-a01.html)[[^]](https://www.mainepublic.org/politics/2026-07-25/troy-jackson-wins-the-democratic-nomination-to-challenge-sen-susan-collins). His background as a resident of northern Maine could help counter Susan Collins' long-held regional advantage [[^]](https://news.ballotpedia.org/2026/07/29/collins-and-jackson-to-face-off-for-the-only-republican-held-u-s-senate-seat-up-for-election-this-year-in-a-state-kamala-harris-won-in-2024/). Jackson also intends to portray Collins as a tool of the ultrawealthy and a Trump supporter in Maine, a state where Kamala Harris won in 2024 [[^]](https://news.ballotpedia.org/2026/07/29/collins-and-jackson-to-face-off-for-the-only-republican-held-u-s-senate-seat-up-for-election-this-year-in-a-state-kamala-harris-won-in-2024/). Following his nomination confirmation in July 2026, polling data from that month indicated his support was around **48%** [[^]](https://www.predictionedge.com/elections/us-senate/maine-race/).

## What public polling data is available for the head-to-head matchup between Collins and Jackson since he became the nominee in July 2026?

Kalshi prediction for Troy Jackson | 64% probability (August 6, 2026) [[^]](https://kalshi.com/markets/kxmesenateperson/maine-senate-winner-person/kxmesenateperson-26)[[^]](https://www.predictionedge.com/elections/state-senate/maine-race-winner-by-party/) |
Election rating | Toss-up or tilt Republican (late July 2026) [[^]](https://news.ballotpedia.org/2026/07/29/collins-and-jackson-to-face-off-for-the-only-republican-held-u-s-senate-seat-up-for-election-this-year-in-a-state-kamala-harris-won-in-2024/)[[^]](https://votes.decisiondeskhq.com/races/2026-11-03/maine-us-senate-general-election) |
Troy Jackson's nomination date | July 25, 2026 [[^]](https://news.ballotpedia.org/2026/07/29/collins-and-jackson-to-face-off-for-the-only-republican-held-u-s-senate-seat-up-for-election-this-year-in-a-state-kamala-harris-won-in-2024/)[[^]](https://news.ballotpedia.org/2026/07/30/troy-jackson-becomes-the-first-replacement-nominee-for-the-u-s-senate-in-maine-since-1918/) |

**Limited public polling data exists for the Collins-Jackson matchup since his nomination**

Limited public polling data exists for the Collins-Jackson matchup since his nomination. As of August 6, 2026, there is an absence of specific public polling data for the head-to-head race between incumbent Susan Collins and new Democratic nominee Troy Jackson [[^]](https://newsnation-votes.decisiondeskhq.com/races/2026-11-03/maine-us-senate-general-election/polling)[[^]](https://uselectionatlas.org/POLLS/SENATE/2026/polls.php?class=2&fips=23)[[^]](https://votes.decisiondeskhq.com/races/2026-11-03/maine-us-senate-general-election/forecast). Troy Jackson officially secured the Democratic nomination on July 25, 2026 [[^]](https://news.ballotpedia.org/2026/07/29/collins-and-jackson-to-face-off-for-the-only-republican-held-u-s-senate-seat-up-for-election-this-year-in-a-state-kamala-harris-won-in-2024/)[[^]](https://news.ballotpedia.org/2026/07/30/troy-jackson-becomes-the-first-replacement-nominee-for-the-u-s-senate-in-maine-since-1918/). Before Jackson's formal nomination, a University of New Hampshire poll conducted from July 15-20, 2026, indicated Troy Jackson led Susan Collins **49%** to **46%** among likely general election voters, with a 2.9 percentage point margin of error [[^]](https://spectrumlocalnews.com/me/maine/politics/2026/07/22/maine-senate-race-poll-shows-statistical-tie-between-jackson-and-collins)[[^]](https://thehill.com/homenews/5983301-jackson-leads-collins-poll/).

Prediction markets and analysts offer differing views on the race outcome. Despite the absence of specific recent polling, prediction markets on Kalshi as of August 6, 2026, listed Troy Jackson as the favorite, assigning him approximately a **64%** **probability** of winning the Maine Senate election, compared to **37%** for Susan Collins [[^]](https://kalshi.com/markets/kxmesenateperson/maine-senate-winner-person/kxmesenateperson-26)[[^]](https://www.predictionedge.com/elections/state-senate/maine-race-winner-by-party/). However, as of late July 2026, analysts generally rated the general election for Maine's U.S. Senate seat as a toss-up or tilt Republican, with forecast models suggesting a narrow advantage for Susan Collins [[^]](https://news.ballotpedia.org/2026/07/29/collins-and-jackson-to-face-off-for-the-only-republican-held-u-s-senate-seat-up-for-election-this-year-in-a-state-kamala-harris-won-in-2024/)[[^]](https://votes.decisiondeskhq.com/races/2026-11-03/maine-us-senate-general-election).

## What does the 2026 advertising spending data from Kantar/CMAG show about the messaging strategies of the Collins and Jackson campaigns?

Jackson's Core Messaging | Identity as a fifth-generation logger, political origin in a 1998 timber protest, and a populist platform against Collins on healthcare, housing, and heating costs [[^]](https://mainemorningstar.com/2026/08/03/troy-jacksons-first-senate-ad-hits-the-airwaves/)[[^]](https://www.nbcnews.com/politics/2026-election/maine-senate-race-democrats-poised-nominate-troy-jackson-challenge-sus-rcna588711)[[^]](https://spectrumlocalnews.com/me/maine/news/2026/07/27/maine-senate-race) |
Collins' Core Messaging | Experience as chair of the U.S. Senate Appropriations Committee, highlighting ability to deliver federal results for Maine [[^]](https://news.ballotpedia.org/2026/07/29/collins-and-jackson-to-face-off-for-the-only-republican-held-u-s-senate-seat-up-for-election-this-year-in-a-state-kamala-harris-won-in-2024/) |
Republican Attack Ad Campaign | Six-figure campaign against Jackson focusing on volatile personality, past conflicts, and verbal abuse [[^]](https://www.nbcnews.com/politics/2026-election/maine-senate-race-democrats-poised-nominate-troy-jackson-challenge-sus-rcna588711)[[^]](https://spectrumlocalnews.com/me/maine/news/2026/07/27/maine-senate-race) |

**Specific advertising spending data from Kantar/CMAG is unavailable**

Specific advertising spending data from Kantar/CMAG is unavailable. Specific advertising spending analysis from Kantar/CMAG for the 2026 Maine Senate race is not included in the provided information [[^]](https://docquery.fec.gov/cgi-bin/forms/C00571703/1996156/se)[[^]](https://www.fec.gov/data/committee/C00916437/)[[^]](https://docquery.fec.gov/cgi-bin/forms/C00314575/1965476/)[[^]](https://docquery.fec.gov/cgi-bin/forms/C00314575/1943203/). However, the available data does detail the initial messaging strategies currently being utilized by both the Collins and Jackson campaigns.

Troy Jackson emphasizes his working-class roots and economic populism. Democratic candidate Troy Jackson's initial advertising strategy centers on his identity as a fifth-generation logger and his political origins, which trace back to a 1998 timber industry protest [[^]](https://mainemorningstar.com/2026/08/03/troy-jacksons-first-senate-ad-hits-the-airwaves/)[[^]](https://www.nbcnews.com/politics/2026-election/maine-senate-race-democrats-poised-nominate-troy-jackson-challenge-sus-rcna588711)[[^]](https://spectrumlocalnews.com/me/maine/news/2026/07/27/maine-senate-race). He is also campaigning on a populist platform, directly criticizing Senator Susan Collins regarding issues such as healthcare, housing, and heating costs. Jackson's message further includes an economic populist angle, portraying Collins as serving the 'ultrawealthy' and pledging to champion working-class individuals against a perceived 'rigged' economic system [[^]](https://news.ballotpedia.org/2026/07/29/collins-and-jackson-to-face-off-for-the-only-republican-held-u-s-senate-seat-up-for-election-this-year-in-a-state-kamala-harris-won-in-2024/).

Senator Collins highlights experience while her allies launch character attacks. Conversely, Senator Susan Collins is highlighting her extensive experience as chair of the U.S. Senate Appropriations Committee, emphasizing her effectiveness in securing federal outcomes for Maine [[^]](https://news.ballotpedia.org/2026/07/29/collins-and-jackson-to-face-off-for-the-only-republican-held-u-s-senate-seat-up-for-election-this-year-in-a-state-kamala-harris-won-in-2024/). Concurrently, the Republican-aligned Senate Leadership Fund has initiated a six-figure attack ad campaign targeting Jackson. These ads focus on character-based narratives, including allegations of a volatile personality, past conflicts with colleagues, and verbal abuse [[^]](https://www.nbcnews.com/politics/2026-election/maine-senate-race-democrats-poised-nominate-troy-jackson-challenge-sus-rcna588711)[[^]](https://spectrumlocalnews.com/me/maine/news/2026/07/27/maine-senate-race).

## What Could Change the Odds

**The 2026 Maine U.S.** Senate election, scheduled for November 3, 2026, features Republican incumbent Susan Collins against Democratic nominee Troy Jackson [[^]](https://ballotpedia.org/United_States_Senate_election_in_Maine,_2026)[[^]](https://news.ballotpedia.org/2026/07/29/collins-and-jackson-to-face-off-for-the-only-republican-held-u-s-senate-seat-up-for-election-this-year-in-a-state-kamala-harris-won-in-2024/)[[^]](https://en.wikipedia.org/wiki/2026_United_States_Senate_election_in_Maine)[[^]](https://news.ballotpedia.org/2026/07/30/troy-jackson-becomes-the-first-replacement-nominee-for-the-u-s-senate-in-maine-since-1918/). This contest is significant as it is the only Republican-held Senate seat up for election in a state won by Kamala Harris in the 2024 presidential election [[^]](https://news.ballotpedia.org/2026/07/29/collins-and-jackson-to-face-off-for-the-only-republican-held-u-s-senate-seat-up-for-election-this-year-in-a-state-kamala-harris-won-in-2024/)[[^]](https://apnews.com/article/maine-senate-platner-collins-0abe847799b9779d604425de03a914de)[[^]](https://www.foxnews.com/politics/democrats-shake-up-collins-faces-toss-up-platner-replacement-must-win-senate-race). Political analysts and polls currently rate the race as a toss-up [[^]](https://news.ballotpedia.org/2026/07/29/collins-and-jackson-to-face-off-for-the-only-republican-held-u-s-senate-seat-up-for-election-this-year-in-a-state-kamala-harris-won-in-2024/)[[^]](https://apnews.com/article/maine-senate-platner-collins-0abe847799b9779d604425de03a914de)[[^]](https://www.foxnews.com/politics/democrats-shake-up-collins-faces-toss-up-platner-replacement-must-win-senate-race).

**A key catalyst for market volatility stems from the recent change in the Democratic nomination.** Troy Jackson was selected as the Democratic nominee on July 25, 2026, replacing Graham Platner, who withdrew from the race on July 10, 2026, following sexual assault allegations [[^]](https://apnews.com/article/maine-senate-susan-collins-platner-troy-jackson-a5f89f03b6a9aace01f4e829befb7809)[[^]](https://news.ballotpedia.org/2026/07/29/collins-and-jackson-to-face-off-for-the-only-republican-held-u-s-senate-seat-up-for-election-this-year-in-a-state-kamala-harris-won-in-2024/)[[^]](https://en.wikipedia.org/wiki/2026_United_States_Senate_election_in_Maine)[[^]](https://news.ballotpedia.org/2026/07/30/troy-jackson-becomes-the-first-replacement-nominee-for-the-u-s-senate-in-maine-since-1918/). Prediction markets and political strategists are closely tracking polling fluctuations in the wake of this candidate replacement [[^]](https://www.foxnews.com/politics/democrats-shake-up-collins-faces-toss-up-platner-replacement-must-win-senate-race)[[^]](https://polymarket.com/event/maine-senate-election-winner)[[^]](https://kalshi.com/markets/senateme/maine-senate-race/senateme-26). Additional catalysts include the candidates' regional appeal and the broader national political environment [[^]](https://www.foxnews.com/politics/democrats-shake-up-collins-faces-toss-up-platner-replacement-must-win-senate-race)[[^]](https://polymarket.com/event/maine-senate-election-winner)[[^]](https://kalshi.com/markets/senateme/maine-senate-race/senateme-26). Upcoming dates include general election campaigning through early November, early voting beginning in mid-October, and Election Day on November 3, 2026 [[^]](https://www.congresscountdown.com/info/election-timeline-2026)[[^]](https://bipartisanpolicy.org/article/the-2026-midterms-key-dates-and-events/).

## Key Dates & Catalysts

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

## Decision-Flipping Events

- The 2026 Maine U.S.
- Senate election, scheduled for November 3, 2026, features Republican incumbent Susan Collins against Democratic nominee Troy Jackson [^] [^] [^] [^] .
- This contest is significant as it is the only Republican-held Senate seat up for election in a state won by Kamala Harris in the 2024 presidential election [^] [^] [^] .
- Political analysts and polls currently rate the race as a toss-up [^] [^] [^] .

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## Historical Resolutions

No historical resolution data available for this series.

## 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

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

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