The most intriguing Senate race of the cycle is Maine. With two weeks to go until election day, Maine midterm odds are the hardest to assess because the usual metrics and standards matter least here. Susan Collins has long defied political gravity as the last remaining Republican Senator in a state won by Kamala Harris, but with a blue wave seemingly poised to crest, can she swim against the tides once again?
The Fallout: From Graham Platner to Troy Jackson
Usually, Senate elections allow a quick, dirty calculation that broadly sorts states into competitive and uncompetitive buckets. In 2024, Maine voted for Harris by 6.9%, while Donald Trump won the popular vote by 1.5% on the same night. With Nate Silver’s latest national generic ballot sitting around D+8.5%, it’s roughly a 10% swing to Democrats nationally, meaning that Maine should be a solidly blue state this year.
Now, that quick-and-dirty calculation has a lot of caveats. Maine is older and whiter, both of which helped Harris in 2024. We know much of the swing to Trump in 2024 came from poorer, younger, non-white voters, and Maine has fewer of them. And we know Trump’s losses since 2024 have come from the voters who swung most strongly to him, which is part of why Trump +14 Texas is more competitive than it should be, but it also means Maine isn’t deep blue. Broadly, you’d expect a generic statewide race to be in the low-to-mid double digits in Maine this year. Fittingly, that’s how Democrats will likely win the Governor’s race.
There’s also the Graham Platner of it all. Platner was the Democratic nominee but dropped out after several controversial allegations surfaced, and the Democratic Party quickly chose longtime state politician Troy Jackson. In so doing, Democrats ended up with one of the better candidates they could have, despite the controversies.
For those of us trying to handicap Maine Senate odds this year, that calculation is basically worthless here. Maine “should have” flipped in 2020, when Joe Biden won the state by 9.1%, or in 2008, when Collins got a whopping 61% on the same day Barack Obama won the state with 57%. Collins’ ability to do what few candidates can largely comes from being an institution in Maine since the 90s. And that means the national picture is of limited value.
But it does have some value.
View all of the current 2026 midterm odds
Enjoying Covers content? Add us as a preferred source on your Google account
The death of the long-term incumbent? Lessons from past cycles
Twenty years ago, Democrats had a blue wave that won them the Senate in a shocking year, and elected a Senate class famous for winning races they had no business winning based on national factors. Montana, Missouri, Ohio, and Pennsylvania all elected Democratic Senators who went on to win at least one more term in office after a Democrat lost the state Presidentially. Missouri flipped in 2018 as Claire McCaskill couldn’t overcome Hillary Clinton’s 19% deficit from two years earlier, while Montana, Ohio, and Pennsylvania elected Donald Trump in 2016 but elected their Senators in 2018. And all three got wiped off the map in 2024, despite outrunning Kamala Harris.
On the Republican side, signs point to declining blue-state overperformance. Dean Heller won Nevada in 2012 despite Obama winning the state, but couldn't win in 2018. Republicans failed to flip a single Senate seat in 2022, though dodgy candidate selection in key races didn’t help, and Cory Gardner lost in 2020 after his 2014 victory as Biden won Colorado. But Collins won by 8 as Biden won by 9, a gap big enough to overcome Maine’s likely lean this year. (Collins’ official win margin is inflated because Maine’s ranked-choice voting process didn’t happen, since she broke 50% of the vote. Had it happened, her margin would likely have fallen by a couple of percent, as more voters chose a left-wing independent over the right-wing one.)
Except ticket splits don’t stay constant. When Jon Tester won in Montana in 2012 on the same ballot as Barack Obama, he outran Obama by 18%. He outran Kamala Harris by 13% the next time he was on a Presidential ballot. Sherrod Brown’s overperformance increased from 3% in 2012 to 7% in 2024. And while he decided not to contest his seat again, Joe Manchin won a Trump +42 state in West Virginia in 2018 before retiring because he had no chance of winning in 2024.
Ticket splits are usually bigger in midterm years, too. Democrats won Ohio, West Virginia, and Montana in 2018 despite losing them badly two years earlier. Collins could be Manchin-esque, putting in one last great midterm performance before getting swept away in a Presidential year. Or she could be Lincoln Chafee, a New England Republican who consistently wins a blue state until an unpopular second-term president starts a war in the Middle East and starts with an approval rating of 3. I wonder why that comparison feels so apt.
If she wins again with all those headwinds, it will be one of the greatest electoral feats in modern American politics, second probably to Manchin’s 2018 win. But the magnitude of the feat also says something about how likely it is to happen.
