Maine Senate race odds 2026: Collins vs. Jackson
Republican Susan Collins, who has held the seat since 1997, faces Democrat Troy Jackson in one of the closest Senate races of 2026.
Troy Jackson (D) wins
Polymarket
74%
At Sikt’s forecast, Nov 3 · now >99%
Sikt’s forecast
Sikt gives Troy Jackson a 66% chance, against 74% on the markets at the time. Latest Sikt Midterm Bench round: Nov 3, 2026.
Sikt’s read
- History favors Collins. She has won all five of her Senate races, and in 2020 she won by 8.6 points although her opponent led nearly every poll. Democrats have not won a Maine Senate race since 1988.
- The polls favor Jackson. All five polling averages put him 3.3 to 5.7 points ahead. The final quality polls agree (UNH +9, AtlasIntel +9, NYT/Siena +6, YouGov +5), and even Rasmussen has him up 3. Only Emerson has Collins ahead, by 2.
- The year favors Democrats. The national generic ballot is about D+9, about 60% of Maine voters disapprove of Trump, and Collins's ratings are underwater. If the count goes to ranked-choice rounds, the declared Democratic write-ins should send their votes to Jackson.
- What holds Sikt back: Collins's record of beating her polls, in 2008 and 2014 as well as 2020. In UNH's poll, 56% of voters still expect her to win, and outside spending leans her way.
- Bottom line: Jackson is about a two-in-three favorite, unchanged from last round. Sikt discounts his lead for Collins's record, so it is a little less sure of him than the market is.
How much will they win by?
Sikt’s middle estimate: Jackson by 3.2 points. Its 80% range runs from Collins by 4.0 to Jackson by 10.1, so the result should land inside it 8 times in 10. Kalshi's margin markets, at the start of the round: Jackson by 2.4 (Collins by 3.5 to Jackson by 10.0).
Margin is the winner’s lead in share of the vote, in percentage points. Round 13, Nov 3, 2026. Scored against the certified result. Every race: 2026 Senate race margins.
Every round
Chance Troy Jackson wins. Market prices are from the same day; the gap is Sikt minus the average of the two markets, in points. Version is the release of Sikt that made the forecast.
| Round | Date | Sikt | Kalshi | Polymarket | Gap | Version |
|---|---|---|---|---|---|---|
| R13 | Nov 3 | 66% | – | 74% | -7 | 1.12 |
| R12 | Nov 2 | 66% | – | 70% | -4 | 1.12 |
| R11 | Oct 31 | 59% | – | 68% | -10 | 1.12 |
| R10 | Oct 29 | 56% | – | 62% | -7 | 1.12 |
| R9 | Oct 27 | 54% | – | 60% | -6 | 1.12 |
| R8 | Oct 24 | 55% | – | 66% | -11 | 1.12 |
| R7 | Oct 21 | 54% | – | 64% | -10 | 1.12 |
| R6 | Oct 18 | 58% | – | 60% | -1 | 1.6 |
| R5 | Oct 15 | 56% | – | 60% | -3 | 1.6 |
| R4 | Oct 12 | 54% | – | 58% | -4 | 1.6 |
| R3 | Oct 9 | 53% | – | 57% | -4 | 1.6 |
| R2 | Oct 3 | 51% | – | 60% | -8 | 1.2 |
| R1 | Sep 30 | 49% | – | 60% | -11 | 1.0 |
Every forecast will be graded against the result. More on the Sikt Midterm Bench. Not financial advice.
The markets
Who will win the Maine Senate race?
| Outcome | Kalshi | Polymarket | Average |
|---|---|---|---|
| Troy Jackson (D) | – | >99% | |
| Susan Collins (R) | – | <1% |
What to know
- Incumbent: Collins won in 2020 even though most polls showed her behind, a reminder that Maine polling has missed before.
- Ranked-choice voting: Maine uses ranked-choice voting in federal general elections, so second preferences can decide a close race.
- Election day is Tuesday, November 3, 2026. Odds usually move most in the final weeks, on polls, early-vote data and news. See all races on the 2026 midterms page.
How these markets resolve
- Kalshi, “Maine Senate winner?”: If a representative of the Republican party is sworn in as a Senator of Maine for the term beginning in 2027, then the market resolves to Yes. Full rules
- Polymarket, “Maine Senate Election Winner”: This market will resolve according to the winner of the 2026 midterm Maine U.S. Senate election, inclusive of any run-offs. A candidate shall be considered to represent a party in the event that he or she is the nominee of the party in question. Full rules
How to read these odds
A price of 30¢ on a contract that pays $1 means the market puts the event at roughly 30%. Prices move with supply and demand, include fees and spreads, and can lean on long shots. When the two markets disagree by more than a few points, check whether their rules or deadlines differ. More in how prediction markets work and the favorite-longshot bias.
FAQ
Who is favored in the Maine Senate race?
As of Nov 4, 2026, Polymarket prices it at >99%. These are market prices, roughly the probability traders are willing to bet on, not a guarantee.
Why do Kalshi and Polymarket show different odds?
They are separate markets with different traders, fees and sometimes different rules or deadlines. A gap of a few points is normal; a large gap is worth checking against each market's rules.
How often are these odds updated?
Sikt refreshes this page from Kalshi's and Polymarket's public data several times a day. The time of the last update is shown at the top.
Are prediction market odds accurate?
Often, but not uniformly. Research on Kalshi finds prices are informative and improve as a market nears its close, but long shots tend to be overpriced (the favorite-longshot bias).
Market data from the public Kalshi and Polymarket APIs, shown for information only. Prices are midpoints or last trades and can be several hours old. Sikt Intelligence is not affiliated with Kalshi or Polymarket. Not financial or investment advice.