FILE - In this June 9, 2020, file photo Sen. Susan Collins, R-Maine, is followed by reporters as she arrives for the weekly Republican policy luncheon on Capitol Hill in Washington. Collins is once again in a pressure cooker over an issue riveting the nation. This time it's the battle over President Donald Trump’s effort to replace the late Justice Ruth Bader Ginsburg on the Supreme Court. (AP Photo/Susan Walsh, File)

WASHINGTON | It’s so on brand for Sen. Susan Collins to be in a pressure cooker over how she’ll vote in a showdown riveting the nation.

This time, it’s the battle over President Donald Trump’s effort to replace the late Justice Ruth Bader Ginsburg on the Supreme Court. It comes six weeks from an Election Day when Trump might lose and Democrats could win Senate control, and it’s further complicating what could be the Maine Republican’s toughest reelection bid as she fights for a fifth term.

Collins said Saturday — a day after Ginsburg, 87, succumbed to cancer — that Ginsburg’s replacement should be nominated “by the President who is elected on November 3rd.” She said the Senate shouldn’t vote until after the election.

On Monday she told reporters that voting after the election is important “if the American people are going to have confidence in the fairness of the system.” She cited Senate Majority Leader Mitch McConnell’s 2016 decision to block President Barack Obama’s effort to fill a court vacancy that occurred nine months before Election Day.

Collins’ comments left Republicans saying she was asserting an independence that Maine voters have long prized.

“Our state and our country need problem solvers,” said Michael Thibodeau, a Republican and former Maine state Senate president. “People who can compromise and see value in others’ ideas and are not driven solely by the most partisan aspects of politics.”

“Senator Collins always does what she thinks is right for Maine and America, no matter which political party is in power,” said Annie Clark, a Collins campaign spokesperson.

Yet some Republicans warn the court fight will be perilous for Collins.

A Maine poll by The New York Times and Siena College, released last week before Ginsburg died, showed Trump substantially trailing Democratic presidential nominee Joe Biden. It also showed a majority wanting Biden to select the next justice, illustrating risks she faces if seen as deferring to Trump’s wishes.

The poll also showed Collins slightly trailing or even with her Democratic rival, Sara Gideon. That underscores how Collins must balance pleasing moderates who’d prefer a Biden pick without alienating Trump backers adamant she toe the line.

“It ties her into a pretzel,” said Dan Eberhart, a major GOP donor to Trump and some Senate candidates, though not directly to Collins. “She needs the base, but she also needs the center or she will lose.”

“She’ll get dinged on by the right, and dinged on by the left,” said Democratic consultant John Lapp.

In a further challenge for Collins, Maine’s political ground is shifting, with Democrats now outnumbering independents. State records show nearly 387,000 Democrats in July and 340,000 “unenrolled” independents, making Democrats the largest voting block since at least the 1980s, according to Maine Secretary of State Matthew Dunlap. Republicans have long trailed both groups.

As one of Congress’ few remaining GOP moderates, Collins, 67, has often found herself in the spotlight on controversial votes.

Unlike most Republicans, she’s supported abortion rights and voted against Trump’s pick to head the Education Department, conservative Betsy DeVos. She was among a handful of Republican senators who voted against Trump’s effort to erase Obama’s health care law in 2017, killing that drive.

Democrats have complained that despite her penchant for publicly agonizing over difficult issues, she too often follows the GOP line. She backed a massive Republican tax cut in 2017.

And in a deal-breaker for Democrats and many #MeToo movement supporters, Collins cast a pivotal vote for Trump nominee Brett Kavanaugh to fill a Supreme Court vacancy in 2018, despite allegations that he’d committed sexual assault while in high school — allegations he denied. She said he’d persuaded her during a meeting that he’d not overturn the court’s Roe v. Wade decision finding abortion legal. Abortion rights advocates say they think he would.

Democrats hope the new nomination fight will remind liberal voters of Collins’ support for Kavanaugh and of cases affecting abortion rights and the health care law, which a court dominated by conservative justices could decide.

Gideon has hammered Collins over Kavanaugh and the tax bill, which opened a window for a legal challenge of Obama’s health care statute. The Supreme Court is expected to hear arguments attacking that law the week after Election Day.

Civil rights, abortion rights and health care “are at stake this November. Mainers and Americans deserve to have their voices heard with the next president and Senate filling the vacancy on the Supreme Court,” Gideon said in a written statement.

Trump is expected to announce his selection by Saturday. With McConnell, R-Ky., saying the Senate will vote on it this year, Democrats and some Republicans say Collins’ carefully worded statements haven’t explicitly ruled out that if forced to vote, she’d support Trump’s nominee.

“People don’t know what she stands for,” said Lauren Passalacqua, spokeswoman for the Democratic Senatorial Campaign Committee, the party’s Senate political arm. Along with her avoidance of saying if she’ll vote for Trump this year, “that question looms over her campaign and is a political problem for her.”

Collins has long had a fraught relationship with Trump. She didn’t support him during the 2016 election because of his “constant stream of denigrating comments.”

Asked Monday on TV’s “Fox and Friends” about Collins’ statements about the court vacancy, Trump said: “I think that Susan Collins is going to be hurt very badly. People aren’t going to take this.”

“This would deflate the conservative base’s desire to fight for her reelection,” said Rick Manning, president of the conservative Americans for Limited Government.

So far, the two sides have spent or planned $96 million in advertising on the Collins-Gideon race with a slight edge for Democrats, according to Kantar/CMAG, an ad data firm. That makes it the sixth most costly Senate contest this year.

In a sign of conservatives’ ambivalence, the Club for Growth hasn’t endorsed Collins but is collecting contributions for her that may total $200,000, said the conservative group’s president, David McIntosh. He said Collins’ remarks indicate “she’s open” to backing a Trump pick, and added, “It’s an important race for keeping the majority.”

Republicans control the Senate 53-47.

Sharp reported from Portland, Maine.