Democratic Gov. Janet Mills is expected to join the growing field of contenders seeking to unseat U.S. Sen. Susan Collins next year.
That’s according to an internal document obtained by the news outlet Axios that reportedly says Mills, who cannot run for reelection to the Blaine House because of term limits, plans to make the announcement Tuesday.
It’s a marked turnaround for Mills, who said earlier this year that she had no plans to run for office once she finishes her stint as governor.
But Mills has become increasingly vocal with her concerns about the agenda of Republicans and the Trump administration.
Since February, Maine has been locked in a fight with President Donald Trump over the rights of transgender students, particularly student athletes. The pair had a heated exchange during a meeting of governors at the White House, and shortly after that, the Trump administration launched numerous investigations into the state over transgender student participation in sports.
The Justice Department has sued Maine for allegedly violating the civil rights of girls. That case is expected to go to trial next year.
In August, Mills said she would decide whether to run for the U.S. Senate by November. Last month, she said she was “seriously considering” running.
Whether Mills would run has been a big question mark looming over the evolving Democratic field, which already includes Sullivan oyster farmer Graham Platner, Maine Beer Co. co-founder Dan Kleban and former End Citizens United vice president Jordan Wood.
Earlier this year, a poll from the University of New Hampshire found Mills had the highest favorability among potential big-name candidates for the Democratic nomination for the 2026 U.S. Senate race.
In the poll, 40% of respondents indicated they would like Mills to run for the U.S. Senate, compared with 36% support for U.S. Rep. Chellie Pingree of the 1st District and 29% for U.S. Rep. Jared Golden of the 2nd District, who faces a possible showdown with former Republican Gov. Paul LePage for the congressional seat.
Collins, a Republican, announced in November she would seek a sixth term in the U.S. Senate.
Collins is the last Republican standing in New England’s congressional delegation, and she could face stiff headwinds in 2026.
In that University of New Hampshire poll, 71% of respondents thought she didn’t deserve another term in the U.S. Senate, including 84% of Democrats and 57% of Republicans. Among independents, just 67% didn’t think voters should return Collins to Washington.
Just 21% wanted her to keep serving in the U.S. Senate, while 8% were uncertain.
Collins’ popularity has suffered during Trump’s two nonconsecutive terms as president. In April, a Morning Consult poll found 51% of Mainers disapproved of her. A follow-up poll released by Morning Consult in July found 54% of Mainers disapproved of her.
But Collins was in a similar situation back in 2020, with polls favoring her Democratic opponent, Sara Giden of Freeport. The Republican from Caribou defied the polls en route to a historic fifth term in the U.S. Senate.
A showdown between Mills and Collins could strain their otherwise cordial relationship. They have known and respected each other for many years, and both of them rose in Maine politics during the 1980s and are oriented toward the center of their parties.
