Simulated voters
4,597
Synthetic Poll · U.S. Senate — Maine 2026
Synthetic Poll · If Graham Platner exits
Maine Senate simulation compares nine potential Democrats against Susan Collins
We simulated nine potential replacements for Graham Platner using profiles of 4,597 registered Maine voters from all 16 counties. The model estimated support for each Democrat against Susan Collins. We tested the method on five certified past Maine elections and adjusted the estimates using Collins–Platner public polling. Richardson and Bellows led Collins by more than the method's typical error; the other matchups were within it.
Counties covered
All 16
Margin of error
±4.1 pts
Validated against
5 certified races
The matchups
Every replacement against Collins
Finding
Heather Cox Richardson had the strongest estimate at Richardson +7; Valli Geiger had the weakest at Collins +2. Most matchups fell within the method's typical error.
Each matchup was simulated separately on the same voter panel to avoid question-order effects. Differences within about 4 points, the reported margin of error*, should be treated as ties.
| Democrat | Result vs. Collins | Read |
|---|---|---|
| Heather Cox RichardsonHistorian, Letters from an American | Richardson +7 | Beats Collins |
| Shenna BellowsMaine secretary of state | Bellows +5 | Beats Collins |
| Jared GoldenU.S. representative, ME‑02 | Golden +2 | Toss‑up |
| Troy JacksonFormer Maine Senate president | Jackson +2 | Toss‑up |
| Patrick DempseyActor, Maine native | Dempsey +1 | Toss‑up |
| Nirav ShahFormer Maine CDC director | Shah +1 | Toss‑up |
| Dan KlebanMaine Beer Company co‑founder | Collins +1 | Toss‑up |
| Jordan WoodFormer congressional chief of staff | Collins +2 | Toss‑up |
| Valli GeigerState representative, Rockland | Collins +2 | Toss‑up |
* The 4.1-point figure comes from past prediction errors. After applying the correction, we compared estimates for five certified Maine elections with their results. The typical miss was about 4.1 points. We treat candidates within that range of each other as tied. This is an empirical error measure, rather than a conventional sampling margin.
Where each candidate wins and loses
Democrats lead among unaffiliated voters and in the 1st District
The table breaks out estimated support by party affiliation, congressional district, and gender. Unaffiliated voters make up a third of Maine's electorate. All nine Democrats led among those voters and in the 1st District; Collins led in the 2nd District in every matchup.
| Democrat | Statewide | Unaffiliated | ME‑01 | ME‑02 | Men | Women |
|---|---|---|---|---|---|---|
| Heather Cox Richardson | D+7 | D+19 | D+13 | C+2 | C+4 | D+9 |
| Shenna Bellows | D+5 | D+16 | D+11 | C+3 | C+6 | D+8 |
| Jared Golden | D+2 | D+13 | D+6 | C+5 | C+4 | D+1 |
| Troy Jackson | D+2 | D+12 | D+7 | C+6 | C+8 | D+4 |
| Patrick Dempsey | D+1 | D+13 | D+6 | C+6 | C+7 | D+3 |
| Nirav Shah | D+1 | D+13 | D+6 | C+7 | C+9 | D+3 |
| Dan Kleban | C+1 | D+10 | D+4 | C+9 | C+10 | D+1 |
| Jordan Wood | C+2 | D+8 | D+3 | C+10 | C+11 | Even |
| Valli Geiger | C+2 | D+8 | D+3 | C+10 | C+12 | Even |
D = the Democrat ahead; C = Collins ahead. All figures use the same calibration adjustment as the statewide estimates.
Testing on past elections
Comparison with five certified Maine elections
Before estimating the 2026 matchups, we simulated five past Maine elections using the same voter panel. The method identified the winner in all five, though it missed the margins shown below. It also captured support for Collins among Democrats and independents who backed Democrats in other races.
| Certified race | Our method’s reading | Actual certified result |
|---|---|---|
| 2024 President (Harris / Trump) | Harris +5 | Harris +7 |
| 2020 President (Biden / Trump) | Biden +15 | Biden +9 |
| 2020 U.S. Senate (Collins / Gideon) | Collins +1 | Collins +9 |
| 2022 Governor (Mills / LePage) | Mills +20 | Mills +13 |
| 2018 Governor (Mills / Moody) | Mills +15 | Mills +8 |
The differences between these estimates and certified results form the basis of the reported error measure.
How it works
Voter profiles, questions, and calibration
Voter sample. We sampled 4,597 registered Maine voters from the national voter file, covering all 16 counties. We weighted the sample to match the electorate's party and demographic composition in each county.
Simulated responses. The model rated each profile's likelihood of supporting the Democrat on a 0-to-10 scale. We ran each matchup separately to avoid question-order effects.
Profile information. The model received age, gender, race or ethnicity, and party registration. It received no names, addresses, or phone numbers. County and district were used to balance the sample and report results. Adding modeled political lean, past turnout, income, and education made estimates slightly less accurate on the five past elections, so we used the smaller set of inputs.
Calibration. Available public polling put Collins and Platner about even, while our simulation put Platner ahead by about 4 points. We subtracted about 4 points from each Democrat's estimate to match that benchmark. A separate correction estimated from past elections was similar.
Candidate familiarity. The model received a short description of each candidate and treated all nine as established figures. Lesser-known candidates might begin a 100-day campaign with less support than these estimates suggest. Their figures assume party support and sufficient voter familiarity.
Run it on your race
Use synthetic polling to compare candidates
The method called 9 of 10 winners in the 2026 New York and Maryland primaries before voting began. Civly uses it to estimate candidate support and test messages from registered-voter profiles.
Run date July 8, 2026 · simulated panel of 4,597 registered Maine voters drawn from the national voter file, all 16 counties · margin of error about 4.1 points, measured from the method’s misses on five certified past Maine elections · all figures use a calibration adjustment based on Collins–Platner public polling available at the time · prepared by Civly.