By THOMAS BEAUMONT and JOEY CAPPELLETTI The Associated Press

WASHINGTON (AP) — Maine Gov. Janet Mills is taking steps toward running for the U.S. Senate in 2026, sources tell The Associated Press, adding another big-name Democrat to the list of candidates expected to vie for key Republican-held seats next year.

Mills, who is term-limited next year, has made calls to prospective campaign managers, according to two sources with direct knowledge of her efforts. They spoke on condition of anonymity because Mills has not formally announced her candidacy.

Democrats would still face a difficult path to regaining the majority in a 2026 midterm election when they need to win a net of four seats, with most of the races on the ballot in states Republican President Donald Trump won comfortably last year.

But in Mills, Democrats would have a two-term governor with a record of winning statewide, in a place where Democrat Kamala Harris defeated Trump in 2024. That could mean a blockbuster race between Mills and five-term Republican Sen. Susan Collins.

Asked about the moves, aides to Mills on Tuesday noted her comments to reporters in Maine last week that she was “seriously considering” a Senate campaign. Mills has said she would announce a decision by mid-November.

Mills would be the latest prominent Democrat who has been reelected to statewide office to jump into a 2026 contest, in what has been a string of good news for the party.

Former two-term North Carolina Gov. Roy Cooper announced his candidacy for an open Senate seat in July, after Republican Sen. Thom Tillis said in June he would not seek a third term. In Ohio, former three-term U.S. Sen. Sherrod Brown announced in August he would run again for Senate, after losing his reelection bid last year.

Trump carried North Carolina last year by 3.2 percentage points. He carried Ohio by 11.3 percentage points.

Mills has a strong track record of winning statewide in Maine, where Harris beat Trump by about 7 percentage points. Mills easily won reelection in 2022, her most recent election, defeating Republican former Gov. Paul LePage by about 13 percentage points.

Mills made national headlines earlier this year after sparring with Trump during a meeting of governors at the White House. Trump singled out Mills during the meeting, pushing her to comply with an order to bar transgender athletes from girls’ and women’s sports and threatening to deny federal funding to the state.

“We’ll see you in court,” Mills said during the back and forth. Trump responded: “Enjoy your life after governor because I don’t think you’ll be in elected politics.”

Though the Democratic nominee has carried Maine in the past nine consecutive presidential elections, Trump has carried Maine’s rural, northern 2nd Congressional District three times. Since 1972, Maine has awarded an electoral vote by congressional district and to the state’s overall winner.

Collins has been a difficult challenge for Democrats since she was elected to the Senate in 1996. Until 2020, when she beat Democrat Sara Gideon by 8.6 percentage points, Collins had won three consecutive reelection campaigns by double digits, including a 37-percentage-point victory in 2014.

Collins has long touted herself in the fiercely independent state as a bipartisan centrist willing to work with both parties. She and a handful of other Republicans were at the table with some Democratic senators in 2009 working on bipartisan health care legislation before talks broke down after that year’s memorably heated August recess demonstrations by opponents of the effort.

More recently, opponents accused her of enabling Trump, pointing to votes to confirm Supreme Court justices who, in 2022, overturned Roe v. Wade, the landmark decision that established a constitutional right to abortion for almost 50 years.

Mills will still need to win a primary that includes oyster farmer Graham Platner, Maine Beer Company co-founder Dan Kleban and Jordan Wood, who was chief of staff to former California Rep. Katie Porter.

Senate Democratic Leader Chuck Schumer of New York is credited with working hard to convince Brown in Ohio to abandon his consideration of a run for governor and instead run for Senate in 2026. Schumer had visited Ohio more than once this year, including dining in Columbus with Brown and his wife, Connie Schultz, on a Friday evening in mid-June.

Schumer spoke with Mills about the Senate race early in the year during a meeting in Washington, but has not visited the state this year.

North Carolina’s Cooper, whose tenure as governor overlapped with Mills’, however, talked with Mills more than once after he entered the Senate race in his state in an effort to urge his colleague from Maine to consider the same move.