Short Answer

Darline Graham is likely to win the 2026 South Carolina Senate race, with the market pricing this outcome at 86.0%.

1. Market Behavior & Drivers

This market, pricing the probability of a Democratic victory in the 2026 South Carolina special Senate election, has remained stable in a low-probability band. The price level is consistent with ratings from The Cook Political Report, Inside Elections, and Sabato's Crystal Ball, all of which categorize the race as "Solid Republican" or "Safe Republican". No Democrat has won a statewide race in South Carolina since 2006.
The market's trading period began the day after Darline Graham won the Republican primary runoff on August 25, solidifying the general election matchup against Democrat Inez Tenenbaum. The opening price of 14% indicates that Graham's nomination did not significantly alter the market's initial assessment of the race as a long shot for Democrats. The subsequent drift from 14% to 13% occurred on low volume and does not coincide with any reported news or developments. This minor price action suggests a slight consolidation of sentiment rather than a reaction to a specific catalyst.
  • Since last update (~34d): Darline Graham's market probability declined by 3.0pp, causing her edge to flip positive.
  • Annie Andrews' model probability increased by 0.4pp; her market remained static.
  • The overall model-market edge for the prediction compressed by 1.8pp.
  • Darline Graham, appointed July 13, 2026, benefits from strong state Republican lean.
  • Annie Andrews holds significant fundraising, but Republican strength limits her 2026 prospects.

Who Wins and Why

Outcome Market Model Why
Annie Andrews 13.0% 13.1% Annie Andrews faces an uphill battle against an entrenched incumbent in a historically red district.
Darline Graham 86.0% 86.9% Incumbent Senator Darline Graham benefits from high name recognition and a strong political track record.

Current Context

The 2026 South Carolina special election fills a vacant Senate seat. This special election follows the death of incumbent Senator Lindsey Graham on July 11, 2026 [1][2]. His sister, Darline Graham, currently holds the seat by appointment and won the Republican nomination in a special primary runoff on August 25, 2026 [1][2][3][4]. The general election is scheduled for November 3, 2026 [1][2][4]. Major candidates include Republican Darline Graham and Democratic nominee Annie Andrews [1][2][5]. Other candidates are Mark Hackett (Constitution), Kasie Whitener (Libertarian), and several independent candidates [1][2].
Darline Graham is favored due to the state's Republican lean. Prediction markets and political analysts widely favor Republican nominee Darline Graham [6][7][8]. This assessment stems from South Carolina's strong Republican orientation; the state supported the Republican presidential candidate by 18 points in 2024 [6][7][8]. Democratic candidates historically face difficulty in statewide races there [6][7][8]. As of September 9, 2026, Decision Desk HQ forecasts the South Carolina Senate race as Likely R [9]. Early voting begins on October 19, 2026, ahead of the November 3, 2026 general election [10][11][12].
Sources (12)
  1. 1United States Senate election in South Carolina, 2026 - Ballotpediaballotpedia.org
  2. 22026 United States Senate election in South Carolina - Wikipediaen.wikipedia.org
  3. 3South Carolina holds special primary to replace Lindsey Graham | AP Newsapnews.com
  4. 4United States Senate election in South Carolina, 2026 (August 25...ballotpedia.org
  5. 5Annie Andrews - Ballotpediaballotpedia.org
  6. 6Brack: Republicans have slight edge in odd race for U.S. Senate - Statehousecharlestoncitypaper.com
  7. 7Annie Andrews’ Chances of Beating Darline Graham in South Carolina - Newsweeknewsweek.com
  8. 8Why Darline Graham Will Win the SC Senate Race: Kalshi | OddsShopperoddsshopper.com
  9. 92026 U.S. Senate Forecast | Decision Desk HQvotes.decisiondeskhq.com
  10. 102026 Election Calendar (scVOTES)scvotes.gov
  11. 112026 Candidate Information - SC Votes - South Carolina Election Commissionscvotes.gov
  12. 12https://scvotes.gov/wp-content/uploads/2026/03/2026-Candidate-Filing-Toolkit-DIGITAL.pdfscvotes.gov

2. Price Chart

Historical Price (Probability)

Outcome probability
Date

3. Market Data

Contract Snapshot

For a given candidate contract, a "Yes" resolution triggers if that candidate's associated party wins the South Carolina Senate election, and a "No" resolution triggers if their party does not win, with the market resolving strictly by the winning party. Trading for this market begins on November 3, 2024, at 8:00 AM EST, and the maximum payout date is November 3, 2027.

Available Contracts

Market options and current pricing

Outcome bucket Yes (price) No (price) Last trade probability
Darline Graham $0.87 $0.14 86%
Annie Andrews $0.14 $0.87 13%

Market Discussion

Incumbent U.S. Senator Darline Graham (R) secured the Republican nomination in an August 25, 2026, primary runoff and will face Democratic nominee Annie Andrews, along with candidates from other parties, in the general election on November 3, 2026 [1][2][3][4][5]. Prediction markets and forecasters consistently favor Darline Graham (R) to win, with implied probabilities for her victory ranging between 85% and 91% as of early September 2026 [6][7][8][9]. While most independent polls show Graham with a comfortable lead, the Democratic campaign has promoted internal polls suggesting a tighter contest to encourage national party investment [9][10].

Sources (10)
  1. 1Sen. Darline Graham wins South Carolina GOP Senate race, defeating Rep. Ralph Normannbcnews.com
  2. 2South Carolina chooses Darline Graham as Republican nominee for US Senate | South Carolina | The Guardiantheguardian.com
  3. 3Four candidates set for South Carolina U.S. Senate race after GOP...live5news.com
  4. 4United States Senate election in South Carolina, 2026 - Ballotpediaballotpedia.org
  5. 52026 South Carolina US Senate Live Election Results | DDHQnewsnation-votes.decisiondeskhq.com
  6. 6South Carolina Senate winner? Odds & Predictions 2026kalshi.com
  7. 7South Carolina Senate Election Winner Predictions & Odds 2026 | Polymarketpolymarket.com
  8. 82026 South Carolina Senate Election: Polls & Odds | Prediction Edgepredictionedge.com
  9. 9Annie Andrews vs. Darline Graham—First Independent Poll Gives Race Update - Newsweeknewsweek.com
  10. 10‘A path to victory’: Democrat Andrews pushes party to invest in South Carolina | Semaforsemafor.com

4. Trust Index

Octagon Trust Index Kalshi 83 Good
How it adds up
Integrity80% of score84Good
Trade quality20% of score79Good

Includes the cost to trade: a $10,000 order loses under 1% of the price to slippage.

Trust score83Good

Weighted blend with hard caps — a critically weak safety pillar, or a severe trading anomaly, caps the total regardless of the rest. Full methodology · About the Trust Index

Trust profile
Integrity4 screens run · 6 don't apply
Market integrity
84Good

Outcome is hard to influence

No suspicious activity on any screen

Screened clean
Large tradesNo single trade dominates the tape. Clear
Thin-volume movesNo significant move Clear
Size patternsTrade sizes look organic. Clear
2 screens not run
Outcome control · doesn't apply to this market type
Thin-leg conviction · doesn't apply to this market type
Info fairness
80Good

Structural prior — no screens apply

No suspicious activity on any screen

Screened clean
Information exposureNo concentrated group can know the outcome materially early. Clear
4 screens not run
Move vs. catalyst · doesn't apply to this market type
Longshot repricing · doesn't apply to this market type
Pre-broadcast certainty · doesn't apply to this market type
Cross-venue timing · doesn't apply to this market type
Resolution quality
92Strong

Resolution mechanism is dependable

No suspicious activity on any screen

Resolution rules read: Clear

Liquidity
82Deep

Size fills near the screen price

2 contracts · worst first

Annie Andrews79
Tradeable · high confidence

Typical bar range 7.7% of price over 8 traded bars

24h traded notional $2,063 · 24h
Darline Graham83
Deep · low confidence

Light recent trading — size may not fill near the screen price.

Move quality
70Stable

No significant moves

2 contracts · worst first

Darline Graham—
No significant move (6h)

Price was stable over the last 6 hours.

Annie Andrews—
No significant move (6h)

Price was stable over the last 6 hours.

Rule clarity
100Clear

Counts toward Resolution quality, not here

2 contracts · worst first

Darline Graham100
Clear · high confidence

All checks pass

objective outcome · Clearofficial source · Cleartime boundary · Clear
Annie Andrews100
Clear · high confidence

All checks pass

objective outcome · Clearofficial source · Cleartime boundary · Clear
Trade quality
79Good

Order book supports trading

Deep and tight enough to trade efficiently.

Outcome quality 82 (notional-weighted across 2 scored legs)

$100 order: 0.5c slippage (<1% of a 87.5c contract)

$1,000 order: 0.5c slippage (<1% of a 87.5c contract)

$10,000 order: 0.5c slippage (<1% of a 87.5c contract)

Darline Graham83Market scoreLiquidity83Move quality–Rule clarity100
Why 83
Liquidity
83 · Deep · low confidence

Light recent trading — size may not fill near the screen price.

Move quality
No significant move (6h)

Price was stable over the last 6 hours.

Rule clarity
100 · Clear · high confidence

All checks pass

objective outcome · Clearofficial source · Cleartime boundary · Clear
Annie Andrews79Market scoreLiquidity79Move quality–Rule clarity100
Why 79
Liquidity
79 · Tradeable · high confidence

Typical bar range 7.7% of price over 8 traded bars

24h traded notional $2,063 · 24h
Move quality
No significant move (6h)

Price was stable over the last 6 hours.

Rule clarity
100 · Clear · high confidence

All checks pass

objective outcome · Clearofficial source · Cleartime boundary · Clear

underwriting_v1.4 · computed Oct 1, 2026

5. What polling data and historical precedents support forecasts favoring Darline Graham in the 2026 special election?

Primary Runoff Vote52.6% (August 25, 2026) [1][2][3]
Prediction Market Odds80 84% for Republican nominee [4][5]
Decision Desk HQ Forecast79% win probability for Darline Graham (as of September 9, 2026) [2][3][6]
Strong forecasts favor Darline Graham in the upcoming special election. Predictions for Darline Graham in the 2026 South Carolina U.S. Senate special election are robustly supported by historical voting patterns, her incumbency, and strong market predictions. While polling data is considered a minor factor in forecast models, South Carolina's consistent Republican leanings provide a substantial structural advantage for the Republican nominee [7][6][8]. Historically, South Carolina is a reliably Republican state, with the Republican party winning every Senate election since 2004 and every presidential election since 1980 [7][9][10].
Darline Graham secured her candidacy through appointment and a primary win. She was appointed as an interim U.S. Senator on July 11, 2026, by Governor Henry McMaster, following the death of her brother, Lindsey Graham [1][7]. She subsequently secured the Republican nomination by winning the August 25, 2026, primary runoff with 52.6% of the vote against Ralph Norman [1][2][3]. Her campaign also received significant backing from former President Donald Trump, including in-person rallies and over $800,000 in super PAC spending [1][7][11].
Prediction markets and forecast models indicate a high probability of her victory. Prediction markets consistently indicate a strong likelihood for the Republican nominee to win the South Carolina Senate seat, with probabilities around 80-84% leading up to the November 2026 general election [4][5]. As of September 9, 2026, Decision Desk HQ forecasts a 79% win probability for incumbent U.S. Senator Darline Graham. This forecast model integrates 70% fundamentals, such as incumbency and partisan baseline, with 5% polling data and 25% market predictions [6][8].
Sources (11)
  1. 1Sen. Darline Graham wins South Carolina GOP Senate... - NBC Newsnbcnews.com
  2. 2United States Senate election in South Carolina, 2026 (August 25...ballotpedia.org
  3. 3United States Senate election in South Carolina, 2026 - Ballotpediaballotpedia.org
  4. 4South Carolina Senate primary odds: Graham's sister opens as heavy favoritenews.kalshi.com
  5. 5Two Races, One Seat: How Prediction Markets Are Pricing the South Carolina Senate Scramble - Prediction Authoritypredictionauthority.com
  6. 62026 South Carolina US Senate Forecast | DDHQvotes.decisiondeskhq.com
  7. 7Darline Graham wins South Carolina GOP nomination to replace her...abc7ny.com
  8. 82026 South Carolina US Senate Forecast | DDHQnewsnation-votes.decisiondeskhq.com
  9. 9Primary runoff will determine Lindsey Graham's (R) replacement on August 25 - Ballotpedia Newsnews.ballotpedia.org
  10. 10Lindsey Graham's death will set off a special primary election for a Senate seat that's open for the second time since 1956 - Ballotpedia Newsnews.ballotpedia.org
  11. 11Bettors Buck the Polls With Shock Darline Graham Prediction - Yahooyahoo.com

6. How do Darline Graham's and Annie Andrews' fundraising totals and cash-on-hand compare ahead of the November 2026 election?

Annie Andrews Cash on Hand$4.1 million as of August 4, 2026 [1]
Darline Graham Cash on Hand$251,000 as of August 5, 2026 [1]
Annie Andrews Total Receipts$10,804,040 as of June 30, 2026 [2][3][4]
Annie Andrews significantly leads Darline Graham in available funds. As of early August 2026, Democratic candidate Annie Andrews reported approximately $4.1 million in cash on hand by August 4, 2026 [1]. In contrast, Republican Darline Graham held approximately $251,000 in cash on hand as of August 5, 2026 [1]. This shows a substantial financial advantage for Andrews ahead of the November 2026 election.
Andrews' campaign shows robust fundraising and spending totals. Her campaign committee reported total receipts of $10,804,040 and total disbursements of $6,684,746 by June 30, 2026 [2][3][4]. These figures indicate considerable financial activity and resource mobilization.
Graham's fundraising lags, with committee historical activity noted. Darline Graham's campaign recorded total receipts of $346,783 as of her August 5, 2026 filing [5]. Her committee also has historical financial activity related to the previous incumbent [5][4].
Sources (5)
  1. 1Follow the Money: South Carolina's 2026 Senate Race | Legis1legis1.com
  2. 2DR. ANNIE ANDREWS FOR SENATE - committee overview | FECfec.gov
  3. 3ANDREWS, ANNIE - Candidate overview - FECfec.gov
  4. 42026 South Carolina US Senate Forecast | DDHQvotes.decisiondeskhq.com
  5. 5FEC Disclosure Form 3 for Team Graham, Incdocquery.fec.gov

7. What potential campaign missteps or external events before November 3, 2026, could plausibly shift momentum away from Darline Graham?

Senate Appointment DateJuly 13, 2026 [1][2][3][4][5][3][6]
Primary Runoff Vote Share52.6% [1][2][7][3][5][3][6][8]
Last Republican Senate Loss in SC2002 [1][7][5][4]
Darline Graham quickly secured her Senate seat and Republican nomination. She was appointed to the U.S. Senate on July 13, 2026, by Governor Henry McMaster, filling the vacancy created by the death of her brother, Senator Lindsey Graham, on July 11, 2026 [6]. Following her appointment, she won a special Republican primary runoff on August 25, 2026, with 52.6% of the vote, thereby securing the Republican nomination for the November 3, 2026, general election [1][2][3][4][5][3][8].
Graham faces scrutiny despite a strong Republican advantage in South Carolina. Her potential vulnerabilities before the November 3, 2026, general election largely stem from pre-existing criticisms that emerged during her primary campaign, including her limited prior political experience and allegations of nepotism [1][7]. Despite these challenges, the Republican nominee is heavily favored to win the general election. South Carolina is considered a deep-red state, and a Republican has not lost a Senate seat there since 2002 [1][7][5][4].
Sources (8)
  1. 1Sen. Darline Graham wins South Carolina GOP Senate... - NBC Newsnbcnews.com
  2. 2Sen. Darline Graham wins GOP nomination for U.S. Senate in... - NPRnpr.org
  3. 3United States Senate election in South Carolina, 2026 - Ballotpediaballotpedia.org
  4. 42026 United States Senate election in South Carolina - Wikipediaen.wikipedia.org
  5. 5United States Senate election in South Carolina, 2026 (August 25...ballotpedia.org
  6. 6U.S. Sen. Darline Graham takes office — ending the vacancy in South Carolina’s class II seat - Ballotpedia Newsnews.ballotpedia.org
  7. 7Darline Graham wins GOP nomination for next US Senate term...scdailygazette.com
  8. 8Darline Graham wins South Carolina GOP nomination to replace her...ap.org

8. What do 2024 presidential election results by county suggest about Graham's and Andrews' likely geographic strongholds in 2026?

Republican Presidential Vote Share (SC)58.2% (Donald Trump) [1]
Democratic Presidential Vote Share (SC)40.36% (Kamala Harris) [2]
Democratic Vote Share (Charleston County)51.9% (Kamala Harris) [1]
South Carolina's 2024 presidential results indicate Republican strength statewide. Donald Trump secured a significant victory, winning 58.2% of the statewide vote and prevailing in the majority of counties [1]. The overall Republican vote share was 58.23%, compared to 40.36% for Democratic candidate Kamala Harris, establishing a strong Republican baseline across most of the state's counties [2]. This suggests Darline Graham, the Republican nominee for the 2026 U.S. Senate election, would find primary support in these predominantly Republican-leaning areas.
Democratic support is concentrated in urban and coastal regions. Kamala Harris demonstrated strength in urban centers during the 2024 presidential election, notably winning 51.9% of the vote in Charleston County and performing well in Fairfield County [1]. This pattern aligns with Annie Andrews' strong performance in the 2026 Democratic primary in urban and coastal areas such as Charleston and Beaufort [3]. These regions represent typical Democratic strongholds in South Carolina that often lean against the state's broader Republican trends, indicating they would be Annie Andrews' likely geographic strongholds in the 2026 election [3].
Sources (3)
  1. 12024 United States presidential election in South Carolina - Wikipediaen.wikipedia.org
  2. 22024 Presidential General Election Results - South Carolinauselectionatlas.org
  3. 32026 South Carolina US Senate Live Election Results | DDHQvotes.decisiondeskhq.com

9. What evidence from Annie Andrews' campaign strategy suggests she could outperform typical Democratic benchmarks in South Carolina?

Andrews Total Receipts$10.8 million (by mid-2026) [1][2]
Opponent Total Receipts$346,783 (as of August 5, 2026) [1][2]
Andrews Probability of Winning21% (Decision Desk HQ as of September 9, 2026) [1][2]
Annie Andrews' campaign strategy positions her to potentially exceed typical Democratic performance in South Carolina. Her approach emphasizes her background as a pediatrician and a "non-career politician" to build trust with voters, focusing on critical issues such as healthcare accessibility and lowering the cost of living [3][4][5][6][7][8]. This strategy aims to broaden her appeal beyond the traditional Democratic base by operating in a "general election" mode, working to unite Democratic voters while also attracting independents and moderate Republicans [4][9][10].
Andrews has demonstrated significant financial strength, outperforming her opponent in fundraising efforts. Her campaign reported over $10.8 million in total receipts by mid-2026, vastly exceeding her opponent Darline Graham's $346,783 as of August 5, 2026 [1][2]. This financial capability is further underscored by robust grassroots fundraising, which has raised $6.5 million and surpassed early projections, indicating a strong infrastructure capable of supporting a competitive statewide race [6][9].
Despite structural challenges, Andrews shows potential to outperform lower probabilistic benchmarks. Forecasting models generally categorize the race as 'Likely Republican' due to structural factors [1][2]. However, recent polling in late August 2026 indicates a competitive contest, with some surveys showing Andrews tied or holding a narrow lead [1][2]. While prediction markets as of September 9, 2026, largely favor the Republican candidate, pricing Andrews at 12%–17% [5][11][12], and Decision Desk HQ giving her a 21% probability of winning [1][2], these competitive poll results suggest she could surpass these initial expectations.
Sources (12)
  1. 12026 South Carolina US Senate Forecast | DDHQvotes.decisiondeskhq.com
  2. 2United States Senate election in South Carolina, 2026 - Ballotpediaballotpedia.org
  3. 3A pediatrician is running for Senate. Can doctors change the...theguardian.com
  4. 4Can Annie Andrews Unseat Graham? Republican SC Senate Odds Fall to 78% | Prediction Huntpredictionhunt.com
  5. 5Democrat at 17% to Win SC Senate Seat After Graham's Death - Polls & Odds | Prediction Huntpredictionhunt.com
  6. 6Two Races, One Seat: How Prediction Markets Are Pricing the South Carolina Senate Scramble - Prediction Authoritypredictionauthority.com
  7. 7Dr. Annie Andrews aims to become South Carolina's first Democratic...wbtv.com
  8. 8Lindsey Graham's Death Transforms the Race for His Democratic...nytimes.com
  9. 9Annie Andrews' Chances of Beating Darline Graham in South Carolinanewsweek.com
  10. 10As GOP Senate primary takes shape, Democrat Andrews staying the...greenvilleonline.com
  11. 11Senate Markets - US Political Oddsuspoliticalodds.com
  12. 12https://robomacro.com/elections/marketsrobomacro.com

10. What Could Change the Odds

Key Catalysts

The 2026 South Carolina U.S. Senate election is scheduled for November 3, 2026 [1][2][3]. Republican incumbent Darline Graham, appointed following the death of her brother Lindsey Graham on July 11, 2026, secured the Republican nomination after an August 25, 2026 runoff [1][2][4][5][6]. She faces Democratic nominee Dr. Annie Andrews, alongside Mark Hackett (Constitution Party), Kasie Whitener (Libertarian), and independent candidates Jack Ellison, Cindy Glaser, Paul Sedletsky, Edward Strunge, and Reece Wright-McDonald; Catherine Fleming Bruce is also running as a write-in Democratic candidate [4][7][8]. As of September 9, 2026, prediction markets and political forecasts consistently rate the seat as likely Republican, with Darline Graham holding win probabilities from 79% to 94.6% [9][10][11]. Decision Desk HQ forecasts the race as Likely Republican [12][13].
Potential upside for Annie Andrews centers on securing independent support, robust suburban turnout, and challenging Republican brand toxicity [14]. However, South Carolina's Republican-leaning partisan baseline and the Republican nominee's incumbency advantage present significant headwinds [14]. The general election on November 3, 2026, remains the final key date for these factors to materialize [4][1][15].

Key Dates & Catalysts

  • Expiration: November 03, 2027
  • Closes: November 03, 2027
Sources (15)
  1. 12026 United States Senate election in South Carolina - Wikipediaen.wikipedia.org
  2. 2Historic SC Senate race set: Graham vs. Dr. Annie Andrews in first all-women matchupwach.com
  3. 32026 United States Senate election in South Carolina — Candidates, Dates & Results | Civic Streamcivicstream.tv
  4. 4United States Senate election in South Carolina, 2026 - Ballotpediaballotpedia.org
  5. 5Primary runoff will determine Lindsey Graham's (R) replacement on August 25 - Ballotpedia Newsnews.ballotpedia.org
  6. 6United States Senate election in South Carolina, 2026 (August 25...ballotpedia.org
  7. 7Annie Andrews - Ballotpediaballotpedia.org
  8. 8Jack Ellison - Ballotpediaballotpedia.org
  9. 92026 South Carolina US Senate Forecastvotes.decisiondeskhq.com
  10. 102026 South Carolina Senate Forecast | Election Odds & Latest Pollspollsmax.com
  11. 112026 South Carolina Senate Winner by Party | Polls & Oddspredictionedge.com
  12. 122026 U.S. Senate Forecast | Decision Desk HQvotes.decisiondeskhq.com
  13. 132026 Election Forecast | DDHQintegration-votes.decisiondeskhq.com
  14. 14Can Annie Andrews beat Darline Graham in SC’s Senate race?postandcourier.com
  15. 152026 United States Senate electionsen.wikipedia.org