U.S. Sen. Susan Collins will announce whether she will run for governor Friday morning, ending extensive speculation about her political future and the shape of the 2018 campaign.

Her decision could prompt others to enter the race, or dash the hopes of candidates who don’t want to take on one of the state’s best-liked politicians.

And in the U.S. Senate, Collins’ possible departure could set in motion a costly and bitterly competitive battle for her seat in 2020.

Shortly after a breakfast speech Friday in Rockport, Collins is expected to hold court with members of the state and national news media to elaborate on her decision.

Rumors that Collins was mulling a run for the governor’s office first surfaced more than two years ago, and Collins confirmed them in April. Maine’s senior senator, who is three years into her fourth six-year term, said she would decide in September but pushed back her deadline as Congress wrangled over Republican efforts to repeal the Affordable Care Act.

In statewide polls, Collins has fetched favorable job approval ratings, including a 67 percent approval rating in a Morning Consult poll in April. A poll of about 700 likely voters released Thursday by Public Policy Polling suggested 55 percent of Maine voters approve of her job performance.

So far, Collins and those closest to her have not indicated, even in background conversations, what she intends to do.

Collins’ national profile has grown in recent months as she has taken stands against President Trump and conservative Republicans in their efforts to repeal and replace the ACA, the landmark health care law ushered in by former President Barack Obama. While Collins opposed and voted against the original law, which was passed by Democratic majorities at the time, she has said repeal proposals would do more harm than good, especially in how they would affect Medicaid.

Rumors that Collins might run for governor surfaced in March 2015, when Democrats offered a bill in the Legislature that would have ended the governor’s ability to fill a vacant U.S. Senate seat. The bill failed, but it fueled speculation that Democrats were worried that Collins would run for governor, allowing Republican Gov. Paul LePage to select someone to complete Collins’ term, which expires in 2020.

Some believed LePage could even appoint himself to the seat, but he ruled that out during an appearance on talk radio this year.

In April, Collins told radio talk show hosts she was “seriously considering” a run for governor, noting she felt she could help improve the state’s economy and create jobs. She also said she believed she could help “heal” the state, which has endured a tumultuous period of controversy and scandalous remarks under the blunt-talking LePage.

Collins is expected to make the announcement either during or after a breakfast speech before about 200 people in the Penobscot Bay Area Chamber of Commerce meeting at the Samoset Resort in Rockport.

Collins’ decision could trigger either an avalanche of potential Republican gubernatorial candidates or an exodus among those who would stand little chance of defeating her.

But she would also have to win the June primary, which would attract conservative Republican voters, many aligned with Trump and LePage.

LePage has said he doesn’t believe Collins would survive a Republican primary and that if she wants to run for governor she would have to do so as an independent.

Meanwhile, Senate colleagues and many supporters have urged her to stay in Washington, where she has gained power and influence as a check against Trump and a conservative agenda.

Collins first visited Washington while in high school, meeting with Maine Sen. Margaret Chase Smith in 1971. She later served as staff there for Sen. Bill Cohen, R-Maine.

During a speech in Skowhegan in May at a library named for Smith, Collins extolled the virtues of bipartisan cooperation, saying, “We need centrists, pragmatists to be as active in shaping the political debate as the energized far left and the aggressive right. We need more fanatical moderates.”

So far, three other Republicans have announced gubernatorial runs, including former Maine Department of Health and Human Services Commissioner Mary Mayhew, state Rep. and House Minority Leader Ken Fredette, and state Sen. Garrett Mason, the Republican majority leader. Mayhew is from South China, Fredette from Newport and Mason from Lisbon Falls. This week, former independent candidate for governor Shawn Moody, the owner of a chain of auto body repair shops, announced he was joining the Republican Party and said he also may seek the party’s nomination.

Scott Thistle can be contacted at 713-6720 or at:

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