# Will the Democrats win the Maine Senate race in 2026? > As of 20 October 2026, Prolepsia puts the chance of yes at 57%. - Forecaster: Prolepsia (https://prolepsia.com) - Forecast made: 2026-10-20 - Question type: Yes / no - Resolves: 2026-11-04 - Status: Open - Forecasts: 1 - Page: https://prolepsia.com/forecasts/sextant-theorem-sonar/will-the-democrats-win-the-maine-senate-race-in-2026 - Open in the app: https://app.prolepsia.com/library/5b5cff26-25c5-42eb-b52e-83c296037bbd ## Forecast - Yes: 57% - No: 43% ## How Prolepsia reasons ## TL;DR The saved forecast is **Yes 56.9%** and **No 43.1%**. The Democratic nominee, Troy Jackson, has a small edge in the direct evidence, especially the late polling average and several October surveys. Susan Collins remains fully capable of winning because Maine has already seen her beat a polling consensus by a wide margin. ## Context This is a direct contest between Democratic nominee Troy Jackson and Republican incumbent Susan Collins. Jackson became the Democratic replacement nominee in July after the original nominee withdrew ([AP News](https://apnews.com/article/a5f89f03b6a9aace01f4e829befb7809)). The ballot is effectively a two-candidate Senate race, so the question is chiefly whether Jackson can hold a narrow polling advantage through Election Day rather than whether a substantial third-party vote changes the outcome ([Suffolk](https://www.suffolk.edu/-/media/suffolk/documents/academics/research-at-suffolk/suprc/polls/other-states/2026/10_14_2026_maine_statewide_marginals.pdf?hash=7FCED62D765CBEF2DB2EFD7ADF0213034C981FE0&la=en)). The race sits in the final two weeks of the campaign. That makes direct measures of vote intention more useful than broad political narratives. But this is also precisely when a narrow polling advantage should be treated as a narrow advantage. The forecast does that: it puts Democrats ahead, without treating the result as settled. ## Evidence The historical backbone is Collins’s record as an unusually strong Maine Republican. In 2020, Collins won 51.0% to Democrat Sara Gideon’s 42.4%, an 8.6-point victory, even though the final polling picture had generally favored Gideon ([RealClearPolling](https://www.realclearpolling.com/polls/senate/general/2020/maine/collins-vs-gideon)). The relevant lesson is not that the same error will recur. The candidates, national setting, electorate, and ballot differ. The lesson is narrower and more useful: a small Democratic polling lead against Collins should carry more uncertainty than a comparable lead against a conventional incumbent. The current public evidence nonetheless leans toward Jackson. RealClearPolling’s late series, using polls fielded from September 23 through October 14, has Jackson at 48.8% and Collins at 47.2%. That is a Jackson margin of 1.6 points ([RealClearPolling](https://www.realclearpolling.com/polls/senate/general/2026/collins-vs-jackson)). Its list contains a mix of Jackson leads, ties, and a Collins lead. The signal is not a one-survey outlier. It is a modest, persistent Jackson advantage. The available late polling history is as follows: | Field dates | Poll | Population / sample | Result | |---|---|---|---| | September 15–22 | NYT/Siena | 619 likely voters | Collins 49%, Jackson 46% ([Siena Research Institute](https://sri.siena.edu/2026/09/24/nytimes-siena-poll-of-likely-voters/)) | | September 17–21 | UNH Pine Tree State Poll | 1,312 likely voters | Jackson 51%, Collins 47% ([Political.org](https://political.org/2026-senate-elections/)) | | September 20–22 | Fabrizio Ward / Impact Research for AARP | 982 likely voters | Jackson 50%, Collins 47% ([AARP](https://www.aarp.org/government-elections/maine-election-poll-2026/)) | | September 23–October 1 | CBS/YouGov | 1,144 registered voters | Jackson 50%, Collins 50% ([CBS News](https://www.cbsnews.com/news/maine-senate-poll-2026-10-02/?ftag=CNM-00-10aab4i&intcid=CNI-00-10aaa3a)) | | September 30–October 5 | Washington Post/Schar School | 800 likely voters | Jackson 50%, Collins 46% ([Washington Post](https://www.washingtonpost.com/politics/2026/10/09/poll-democrat-troy-jackson-narrowly-leads-susan-collins-maine-senate-race)) | | October 1–4 | Marist | 1,505 registered voters | Jackson 51%, Collins 47% ([Marist](https://maristpoll.marist.edu/polls/midterm-elections-in-maine-october-2026/)) | | October 5–8 | Rasmussen | 804 likely voters | Jackson 49%, Collins 47% ([Rasmussen Reports](https://ec2-3-16-228-157.us-east-2.compute.amazonaws.com/public_content/politics/elections/election_2026/election_2026_maine_senate)) | | October 8–11 | Suffolk | 500 likely voters | Jackson 49%, Collins 47% ([Suffolk](https://www.suffolk.edu/academics/research-at-suffolk/political-research-center/polls/other-states)) | | October 13–14 | InsiderAdvantage | 1,200 likely voters | Jackson 49%, Collins 47% ([US Polling Data](https://uspollingdata.com/races/senate/maine/)) | The table shows why Jackson is favored but not by much. The newest three listed polls all show Jackson ahead by two points. Washington Post/Schar and Marist show larger Jackson leads. Yet CBS/YouGov is tied, and NYT/Siena gives Collins a three-point lead. The most defensible reading is a close race with Jackson a little ahead, not a race in which polling establishes a stable multi-point Democratic lead. Suffolk is especially useful because it surveyed likely voters late in the campaign and used live telephone interviews. Its Jackson 49%–Collins 47% result included 3.8% undecided and 0.2% refusing ([Suffolk](https://www.suffolk.edu/-/media/suffolk/documents/academics/research-at-suffolk/suprc/polls/other-states/2026/10_14_2026_maine_statewide_marginals.pdf?hash=7FCED62D765CBEF2DB2EFD7ADF0213034C981FE0&la=en)). Its sample size also limits what can be inferred from two points. The result supports a slight Jackson edge. It cannot rule out a narrow Collins lead. The state environment gives Jackson support. Marist found Trump at 40% approve and 59% disapprove among Maine registered voters. It also found Democrats ahead 54%–45% on the generic congressional ballot ([Marist](https://maristpoll.marist.edu/polls/midterm-elections-in-maine-october-2026/)). The same survey placed the Democratic gubernatorial candidate 12 points ahead, while Jackson led Collins by four. That gap shows that the state is not treating this Senate race as a simple referendum on national party control. The Washington Post/Schar survey points in the same direction. It reported a 36% Trump approval rating among likely voters and found a 55% preference for Democratic Senate control. It also found Jackson ahead on several issue measures, including abortion, cost of living, health care, corruption, and understanding Maine voters ([Washington Post](https://www.washingtonpost.com/politics/2026/10/09/poll-democrat-troy-jackson-narrowly-leads-susan-collins-maine-senate-race)). These are favorable conditions for a Democratic challenger. They help explain why Jackson is ahead rather than tied or behind. But Collins has a personal-vote cushion that the generic environment does not capture. CBS/YouGov found that she won support from roughly one in five voters who disapproved of Trump, and that some voters supporting the Democratic gubernatorial nominee were splitting their tickets for Collins ([CBS News](https://www.cbsnews.com/news/maine-senate-poll-2026-10-02/?ftag=CNM-00-10aab4i&intcid=CNI-00-10aaa3a)). Collins also led on bringing federal funding to Maine and on bipartisanship in Washington Post/Schar polling ([CBS News](https://www.cbsnews.com/news/maine-senate-debate-collins-jackson-trump/?ftag=CNM-00-10aab4i&intcid=CNI-00-10aaa3a)). Those are practical reasons a voter can dislike national Republicans and still back the incumbent. Late-campaign indicators are mixed. Party enrollment in returned absentee ballots leaned Democratic: a tracker using the Maine Secretary of State’s October 16 file reported roughly 53% Democratic-enrolled returns, 19% Republican-enrolled returns, and 25% unenrolled returns ([Call the Map](https://www.callthemap.com/early-vote?state=me)). This is mildly favorable to Jackson. It is not a vote count. Maine has many unenrolled voters, and Collins has demonstrated appeal beyond registered Republicans. Money is a small Collins-positive factor. Jackson raised nearly $20.4 million after becoming nominee, but ended September with less cash on hand than Collins and about $1 million in debt. Collins held just under $5.4 million in cash ([News From The States](https://www.newsfromthestates.com/article/jackson-outraises-collins-has-less-cash-left)). Republican-aligned outside spending against Jackson has also been substantial ([PaidForPolitics](https://paidforpolitics.com/races/me-senate)). Resources can matter at the margin, especially in a close late race, but the polling available after that spending still shows Jackson narrowly ahead. The October 15 debate incident, in which Jackson told Collins to “shut up,” is another small Collins-positive risk rather than a decisive event ([AP News](https://apnews.com/article/f5b57cd89178c1625e80b33ecd039c55)). It could provide an effective message for voters focused on demeanor. There is no direct evidence in the supplied record that it has moved the ballot. It should therefore widen caution, not displace the more informative direct vote data. ## What's non-obvious The obvious read is that a Democratic statewide environment should make Jackson comfortably favored. That misses the difference between Maine’s party climate and this candidate matchup. The generic ballot, Trump approval, and governor’s race all look better for Democrats than the Senate ballot does. Collins’s crossover vote is the reason. The forecast gives Democrats the edge because the Senate polls themselves lean Jackson, but it does not use the broader environment as if it were a substitute for the Senate vote. The other easy mistake is to replay 2020 mechanically. Collins’s polling outperformance is genuine and highly relevant. But subtracting the full 2020 error from Jackson’s current margin would assume that every source of that miss repeats. The cleaner interpretation is that 2020 raises the chance that a narrow Jackson lead is misleading. It does not erase the current run of October polling that favors Jackson. ## Uncertainties The largest uncertainty is correlated polling error. The polls are not independent draws from separate electorates. They may share errors in measuring turnout, nonresponse, or Collins’s crossover support. This matters far more when the average lead is 1.6 points than when it is large. Several specific gaps remain: - There is no confirmed post-debate poll in the supplied evidence, so the effect of the October 15 exchange cannot be measured directly. - Absentee-return data identify party enrollment, not candidate choice. They are especially incomplete as a guide to a race involving Collins and many unenrolled voters. - The latest finance information covers activity through September 30, leaving uncertainty about final-week advertising and field activity. - The NYT/Siena Collins lead and the other polls pointing to Jackson cannot be reconciled with certainty from the available material. These uncertainties are why the forecast remains **Yes 56.9%** and **No 43.1%**, rather than a stronger Democratic probability. The available evidence says Jackson has the better chance. It also says Collins has a clear and credible path to win. ## Forecast history | Date | Forecast | |---|---| | 2026-10-20 | 57% chance of yes | ## Sources Prolepsia read - Domain Expert Search - Connection List Tools - [json-schema.org](https://json-schema.org/draft/2020-12/schema) - Realclearpolling - Connection Call Tool - [app.notion.com](https://app.notion.com/p/3fe358b4482d81239fcbe6edfc9143cc?pvs=204) - [app.notion.com](https://app.notion.com/p/3fe358b4482d81d3b031f351e4008b63?pvs=204) - [app.notion.com](https://app.notion.com/p/3fe358b4482d814693d2ceef28a0b520?pvs=204) - [app.notion.com](https://app.notion.com/p/3fe358b4482d8139a1daf396c9841fa5?pvs=204) - [app.notion.com](https://app.notion.com/p/3fe358b4482d81e7a7b8eee3bda96c4b?pvs=204) - [app.notion.com](https://app.notion.com/p/3fe358b4482d81d78baaf5a582bafbc2?pvs=204) - [app.notion.com](https://app.notion.com/p/3fe358b4482d81719517d62c50466f47?pvs=204) - [app.notion.com](https://app.notion.com/p/3fe358b4482d81518a2dd0955673d97d?pvs=204) - [app.notion.com](https://app.notion.com/p/3fe358b4482d81d1a510f3655c6539e5?pvs=204) - [app.notion.com](https://app.notion.com/p/3fe358b4482d81e596d2c47f1c72fa80?pvs=204) - Domain Expert Research Task - [10_14_2026_Maine Statewide Likely Voters](https://www.suffolk.edu/-/media/suffolk/documents/academics/research-at-suffolk/suprc/polls/other-states/2026/10_14_2026_maine_statewide_marginals.pdf?hash=7FCED62D765CBEF2DB2EFD7ADF0213034C981FE0&la=en) - [2020 Maine Senate - Collins vs. Gideon \| RealClearPolling](https://www.realclearpolling.com/polls/senate/general/2020/maine/collins-vs-gideon) - [apnews.com](https://apnews.com/article/5819010ccb7cc4ecf9b1059d21c50ec2) - [apnews.com](https://apnews.com/article/931a9607daf826f2b0f96bb4fab5a514) - [maine.gov](https://www.maine.gov/sos/elections-voting/absenteelayout) - [2026 Senate Elections: Every Race, Live — Political.org](https://political.org/2026-senate-elections) - [Voter Data \| SOS](https://www.maine.gov/sos/elections-voting/voter-data) - [maine.gov](https://www.maine.gov/sos/node) - [Early vote tracker: who has voted so far in 2026 · Call the Map](https://www.callthemap.com/early-vote?state=me) - [fec.gov](https://www.fec.gov/data/candidate/S6ME00464?cycle=2026) - [The Latest: AP-NORC poll: Strong majority of voters believes Trump is failing at home and abroad](https://apnews.com/article/18131f88e983086649e6bf9928cb50f5) - [fec.gov](https://www.fec.gov/data/committee/C00920389) - [Maine Senate 2026: outside spending for and against Troy Jackson and Susan Collins \| PaidForPolitics](https://paidforpolitics.com/races/me-senate) - [suffolk.edu](https://www.suffolk.edu/-/media/suffolk/documents/academics/research-at-suffolk/suprc/polls/other-states/2026/10_14_2026_maine_press_release.pdf?hash=8C53F997AB2A29EAB66252DA2D5B6054FFEDBBDA&la=en) - [NYTimes/Siena Poll of Likely Voters – Siena Research Institute](https://sri.siena.edu/2026/09/24/nytimes-siena-poll-of-likely-voters) - News - [2026 United States Senate election in Maine](https://en.wikipedia.org/wiki/2026_United_States_Senate_election_in_Maine) - [voteclock.org](https://voteclock.org/maine-candidates-on-the-ballot-2026) - [aarp.org](https://www.aarp.org/states/maine/collins-jackson-senate-2026-q-and-a) - [Maine Democratic delegates choose Troy Jackson as new nominee to face US Sen. Susan Collins \| AP News](https://apnews.com/article/a5f89f03b6a9aace01f4e829befb7809) - [maine.gov](https://www.maine.gov/sos/elections-voting/upcoming-elections) - [maine.gov](https://www.maine.gov/sos/sites/maine.gov.sos/files/inline-files/2026%20Candidates%20Guide%20to%20Ballot%20Access%20Final.pdf) - [Home of the Marist Poll \| Polls, Analysis, Learning, and More](https://maristpoll.marist.edu/polls/midterm-elections-in-maine-october-2026) - [AARP Poll: Incumbent Collins Lags in Maine Senate Race](https://www.aarp.org/government-elections/maine-election-poll-2026) - [Other States Polls - Suffolk University Political Research Center - Suffolk University](https://www.suffolk.edu/academics/research-at-suffolk/political-research-center/polls/other-states) - [sethjlevyhub.github.io](https://sethjlevyhub.github.io/fl-early-vote/me.html) - [Troy Jackson tells Susan Collins to 'shut up' during Maine debate \| AP News](https://apnews.com/article/f5b57cd89178c1625e80b33ecd039c55) - [en.wikipedia.org](https://en.wikipedia.org/wiki/2026_United_States_Senate_elections) - [aarp.org](https://www.aarp.org/press/releases/2026-10-01-new-aarp-maine-poll-older-voters-could-play-decisive-role-in-closely-watched-senate-governor-races) - [2020 United States Senate elections](https://en.wikipedia.org/wiki/2020_United_States_Senate_elections) - [mainecounties.org](https://www.mainecounties.org/uploads/1/4/3/2/143228552/2014_gen_election_recap_nov_5.pdf) - [theatlantic.com](https://www.theatlantic.com/politics/2026/10/susan-collins-maine-debate-troy-jackson/689037) - [apnews.com](https://apnews.com/article/78421c0b1708c45e1c2ae9270d9ac630) - [2026 Maine Senate - Collins vs. Jackson \| RealClearPolling](https://www.realclearpolling.com/polls/senate/general/2026/collins-vs-jackson) - [maristpoll.marist.edu](https://maristpoll.marist.edu/wp-content/uploads/2026/10/Marist-Poll_Maine-NOS-and-Tables_202610051032xtc92617B.pdf) - [Jackson outraises Collins, but has less cash left \| News From The States](https://www.newsfromthestates.com/article/jackson-outraises-collins-has-less-cash-left) - [apnews.com](https://apnews.com/article/a9a69ffef493629778dc7fbba931add9) - [maine.gov](https://www.maine.gov/sos/elections-voting/resources-for-ranked-choice-voting) - [projectcuria.com](https://projectcuria.com/elections/me/senate) - [election.org](https://www.election.org/results/2020/maine) - [d3nkl3psvxxpe9.cloudfront.net](https://d3nkl3psvxxpe9.cloudfront.net/documents/ttw_me_20260902.pdf) - [535.wtf](https://535.wtf/races/senate-2026-me) - [battlegrounds.coefficient.org](https://battlegrounds.coefficient.org/me) - [washingtonpost.com](https://www.washingtonpost.com/politics/2026/10/09/poll-democrat-troy-jackson-narrowly-leads-susan-collins-maine-senate-race?pwapi_token=eyJ0eXAiOiJKV1QiLCJhbGciOiJIUzI1NiJ9.eyJyZWFzb24iOiJnaWZ0IiwibmJmIjoxNzkxNTE4NDAwLCJpc3MiOiJzdWJzY3JpcHRpb25zIiwiZXhwIjoxNzkyOTAwNzk5LCJpYXQiOjE3OTE1MTg0MDAsImp0aSI6IjE4NjJkMzQ0LWQ0ZmMtNGIyMy05NzAwLTgwNWU1YTNjMWZlNCIsInVybCI6Imh0dHBzOi8vd3d3Lndhc2hpbmd0b25wb3N0LmNvbS9wb2xpdGljcy8yMDI2LzEwLzA5L3BvbGwtZGVtb2NyYXQtdHJveS1qYWNrc29uLW5hcnJvd2x5LWxlYWRzLXN1c2FuLWNvbGxpbnMtbWFpbmUtc2VuYXRlLXJhY2UvIn0.2_6lAaaYMcbP0y7_Ioe4GYgRcQnYJkY6IAE55nzmhAs) - [cbsnews.com](https://www.cbsnews.com/news/maine-senate-poll-2026-10-02) - [rollcall.com](https://rollcall.com/2026/10/16/senate-democrats-fundraising-third-quarter-elections) - [election.org](https://election.org/election/2026/us-senate/maine) - [Ranked Choice Voting Information and Rules \| SOS](https://www.maine.gov/sos/elections-voting/upcoming/ranked-choice-voting-tabs) - [Maine Senate Race 2026 Polls: Troy Jackson leads](https://uspollingdata.com/races/senate/maine) - [Election 2026: Maine Senate - Rasmussen Reports®](https://ec2-3-16-228-157.us-east-2.compute.amazonaws.com/public_content/politics/elections/election_2026/election_2026_maine_senate) - [Democrat has edge over Susan Collins in critical Maine Senate battle, poll finds - The Washington Post](https://www.washingtonpost.com/politics/2026/10/09/poll-democrat-troy-jackson-narrowly-leads-susan-collins-maine-senate-race) - [CBS News poll finds voters split on state v. national focus in tied Maine Senate race - CBS News](https://www.cbsnews.com/news/maine-senate-poll-2026-10-02?ftag=CNM-00-10aab4i&intcid=CNI-00-10aaa3a) - [2024 Presidential General Election Results - Maine](https://uselectionatlas.org/RESULTS/state.php?f=0&fips=23&year=2024) - [In Maine Senate debate, Collins says she's "not exactly" Trump's "favorite senator" - CBS News](https://www.cbsnews.com/news/maine-senate-debate-collins-jackson-trump?ftag=CNM-00-10aab4i&intcid=CNI-00-10aaa3a) - [Susan Collins’ 2026 Polls Compared With Her 2020 Maine Victory - Newsweek](https://www.newsweek.com/susan-collins-maine-senate-polls-2020-comparison-12534004) - [2026 Maine Senate - Collins vs. Platner](https://www.realclearpolling.com/polls/senate/general/2026/maine/collins-vs-platner) - [October 14, 2026](https://www.suffolk.edu/-/media/suffolk/documents/academics/research-at-suffolk/suprc/polls/other-states/2026/10_14_2026_maine_press_release.pdf) - [Maine Senate race odds and predictions 2026](https://news.kalshi.com/p/maine-senate-race-odds) - [2026 Maine Senate Election: Polls & Odds](https://www.predictionedge.com/elections/us-senate/maine-race) - [2026 Maine Senate Polls](https://www.pollsmax.com/senate/maine) - [Charlie Cook: Susan Collins Now Favorite to Win Maine](https://www.yahoo.com/news/politics/articles/charlie-cook-susan-collins-now-155318038.html) - [Maine Senate polling as Susan Collins, Troy Jackson clash over data centers in debate](https://www.newsweek.com/maine-senate-polling-susan-collins-troy-jackson-head-third-debate-12561510) - [Maine Poll Gives Susan Collins Lead Over Troy Jackson for First Time - Newsweek](https://www.newsweek.com/susan-collins-troy-jackson-maine-senate-race-poll-12482806) - [ME Senate 2026](https://www.cookpolitical.com/senate/race/488601) - [Map shows Republican chances of losing Senate two weeks before midterms](https://www.yahoo.com/news/politics/articles/map-shows-republican-chances-losing-222333657.html) - [Maine Senate Polls and Forecast 2026: Jackson vs Collins](https://www.poliwave.com/us/me/sen-fed) - [Susan Collins Could Be Saved by Kamala Harris Voters - Newsweek](https://www.newsweek.com/susan-collins-could-be-saved-by-kamala-harris-voters-12590840) - [Troy Jackson holds slim lead over Susan Collins for Maine Senate: AARP poll](https://thehill.com/homenews/campaign/6123742-troy-jackson-susan-collins-maine-aarp-poll) - [FiftyPlusOne - Maine General Senate Election Polls and Average for the 2026 General Election](https://fiftyplusone.news/polls/senate/general/maine) - [Troy Jackson Narrowly Leads in Maine Senate Race](https://politicalwire.com/2026/10/14/troy-jackson-narrowly-leads-in-maine-senate-race) - [Susan Collins and Troy Jackson in a tie in poll before final debate](https://www.foxnews.com/politics/collins-insists-socialist-rival-wont-beat-her-maines-money-machine-youll-lose-big-time) - [Jackson +2 Over Collins In New Maine Senate Poll - Joe.My.God.](https://www.joemygod.com/2026/10/jackson-2-over-collins-in-new-maine-senate-poll) - [Latest Polls for Maine Senate: Susan Collins, Troy Jackson Prep for Fourth Debate - Newsweek](https://www.newsweek.com/maine-senate-polling-as-susan-collins-troy-jackson-head-into-fourth-debate-12569146) - [2008 United States Senate election in Maine](https://en.wikipedia.org/wiki/2008_United_States_Senate_election_in_Maine) - [2016 Maine Senate election](https://en.wikipedia.org/wiki/2016_Maine_Senate_election) ## The question Imported from Polymarket. This yes/no question comes from a single Polymarket market. ### How it resolves 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. Candidates other than the Democratic or Republican nominee (e.g., Greens, Libertarian, independent) may be added at a later date. Candidates who run as independents will not be encompassed by the “Democrat” or “Republican” options regardless of any affiliation they may have with the party. The candidates may be named in the contract for the convenience of traders. In the event that any named candidate is replaced as the nominee of their respective party prior to election day, the name in the contract will be updated and the market will resolve based on the replacement nominee of the party. The resolution source for this market is the Associated Press, Fox News, and NBC. This market will resolve once all three sources call the race for the same candidate. If all three sources haven’t called the race in this state for the same candidate, this market will resolve based on the official certification. --- Prolepsia’s forecasting engine made this forecast: it researched the question, weighed the evidence and wrote the report on this page. A probability is not a promise; this one changes as the evidence does.