Who’s Who in Maine’s Competitive Senate Race?

October 28th, 2025
Lindsey Zhao

Although there will be at least 6 seriously competitive Senate races in 2026, Maine’s current race is receiving an inordinately large amount of attention. Susan Collins, a Republican senator first elected in 1996 and re-elected in 4 straight races since then, is likely to face an intimidating Democratic challenger—but who that will be is still uncertain.

Susan Collins has a reputation as a GOP moderate who often votes across party lines, which has likely contributed to her status as the only Republican senator still in office in a Democratic-leaning state. Yet, this may contribute to her political downfall. Democrats now see her seat as one of their best shots to flip a Senate seat in the upcoming midterms. A Democratic super PAC survey recently revealed that Collins has a 61% disapproval rating, and she is increasingly unpopular with both Republicans and Democrats over her approach with President Donald Trump: 81% of Harris voters think she votes with Trump too often, and 73% of Trump voters think she doesn’t vote with Trump often enough.

One reason she may yet survive is the increasingly divisive Democratic primary that will eventually decide who she runs against. Although there are currently six or seven formally declared candidates, the two leading the race are first-time politician Graham Platner and popular, term-limited Maine Governor Janet Mills.

Quick overview of both candidates:

Graham Platner, 41: oyster farmer and veteran. First time running for office. Widely viewed as a breakout progressive candidate, he has raised $4 million for his campaign in less than 2 months and gained the endorsement of left-wing politicians like Bernie Sanders (I-VT). Has recently come under fire for a chest tattoo resembling a Nazi tattoo, which he has since apologized for and covered up, and controversial Reddit comments between 2013-2021 that disparaged police, rural Americans, and LGBTQ+ people.
Janet Mills, 77: current governor of Maine, well-liked and elected by wide margins in the last 2 elections. Seen as an establishment candidate, supported by the Democratic Senate campaign arm. If elected, she would be the oldest-ever freshman Senator in history at 79 years old.

A University of New Hampshire Survey Center poll from around the same time as the Reddit reports surfaced found that 58% of planned voters in the 2026 Democratic primary say they will vote for Platner, while 24% would cast a vote for Gov. Mills. Following revelations about Platner’s past remarks, the numbers have shifted: a newer poll from SoCal Strategies revealed 59% support for Mills, with only 29% continuing to support Platner.

Many rank-and-file Democrats, like Sen. Chris Van Hollen (D-MD) and Maine Sen. Angus King (a left-leaning independent), have declined to give their opinions on whether Platner should drop out, a reflection of his continued popularity among many Americans. Others have publicly maintained their support, like Senator Sanders, while others have withdrawn from their associations with him: Platner’s political director has resigned.

Platner has since apologized for his past remarks and Nazi-affiliated tattoo, saying he had retained the “crude humor…and dark, dark feelings…of the infantry” and had been struggling with PTSD and depression. He also said he had gotten the tattoo while drunk with fellow infantrymen in Croatia and didn’t know of its Nazi affiliations, although he has covered them up since then.

Platner is most popular among self-described socialists, progressives, and moderates, as well as all age categories except those 65+. Many political experts have regarded the votes as indicative of a wider backlash against Mills’ age and the Democratic establishment, which has been in the “political wilderness” since former Vice President Kamala Harris’s loss to President Donald Trump in 2024. The United Auto Workers has also endorsed Platner.

However, Gov. Mills could still pose a serious challenge to Platner’s success. She was initially pushed to enter the race by Senate Minority Leader Chuck Schumer, with the default approval of the Democratic Senate campaign arm. Platner may yet suffer more long-term consequences from his old Reddit posts and Nazi-associated tattoo. Mills also has sizable support from voters over 65, an important fact given that Maine is the oldest state in the US.

If Democrats want to win back the Senate in 2026, they have to earn 4 Senate seats, making a Maine victory all but indispensable to their goals. Yet, no matter who wins, the infighting within the Democratic Party will likely prove damaging in the general race against Susan Collins. How damaging, though, has yet to be seen: the Center for Politics has moved Maine’s rating from “Leans Republican” to “Toss-up” as of October 14, indicating that there is still a lot that could change from now and June 2026.