A bruising Senate confirmation fight over President Donald Trump’s Supreme Court choice may seal the fates of several incumbent senators in the November election, though it has yet to drastically alter the odds for which party will control the chamber.

Trump’s decision to nominate Judge Amy Coney Barrett to the high court with just weeks to go before Election Day has mostly hardened existing partisan lines, which favor Democrats gaining a slim Senate majority on Nov. 3.

Jessica Taylor, Senate editor of the Cook Political Report, and other analysts said that while views could shift once confirmation hearings get under way, initial signs show the basic shape of the contest for Senate control hasn’t changed.

“This is still a map where Republicans remain almost entirely on defense, and Democrats have expanded their offensive opportunities,” she said.

At least three of the most vulnerable Senate incumbents may see their narrow chances of re-election further diminished.

Republicans Susan Collins in Maine and Cory Gardner in Colorado were already running behind their challengers in states Democrat Hillary Clinton won in 2016 and where Democrat Joe Biden has a significant lead. They now face the prospect of a highly motivated Democratic base turning out to vote. In Alabama, Democrat Doug Jones was already struggling in one of the most Republican states in the country, and his opposition to proceeding with Barrett’s confirmation could limit his crossover appeal.

For a handful of Republican senators in tight races in Republican-leaning states, a Supreme Court fight could galvanize Trump’s voters behind them. That includes Martha McSally in Arizona, Joni Ernst in Iowa, Thom Tillis in North Carolina, Steve Daines in Montana and Lindsey Graham in South Carolina. Democrats are seeking to counter that by focusing the fight on the future of Obamacare, and they’ve reported tens of millions in donations since Ginsburg’s death.

Here’s how the confrontation is playing in some key Senate battlegrounds:

Graham in Spotlight

Democrats quickly attacked Graham -- who as chair of the Judiciary Committee will lead hearings on Barrett’s nomination -- as hypocritical on the court vacancy. After Majority Leader Mitch McConnell had refused to consider then-President Barack Obama’s nomination to fill a vacant seat in the 2016 election year, Graham on multiple occasions said he would wait until after the election to consider a Supreme Court pick in the final year of Trump’s term. But after Ruth Bader Ginsburg’s death, he reversed himself and backed a lightning-strike confirmation.

Graham’s switch brought a flood of donations to his already well-funded challenger, Jaime Harrison, who was tied with Graham in two recent polls taken before and after Ginsburg’s passing. Harrison had already raised US$14 million in the second quarter, against US$8.4 million for Graham. While Graham ended June with about US$5 million more in cash on hand Harrison has been touting continued hauls of donations, including US$10.6 million in August. He said he raised US$1 million in a day after a Quinnipiac poll showed him tied with Graham about two weeks ago.

And in a sign national Democrats see the race as a real target, the leadership-aligned Senate Majority PAC announced Monday it would spend US$6.5 million on the race as well.

“I’m getting killed financially,” the three-term incumbent senator said on Fox News, making an unusual plea to viewers for campaign cash.

South Carolina may be in play, but it’s still a tough climb for Biden and the Democrats. Trump won there by 15 percentage points in 2016, and leads Biden in the state. He may yet help carry Graham over the line.

Caught in Between

In Maine, Collins found in 2018 that her backing for Trump’s previous Supreme Court pick, Brett Kavanaugh, accelerated the collapse of her support among Democrats. She’s still paying the price, even though she’s said that Ginsburg’s successor should be picked by the winner of the presidential election.

“Collins’s race was already about the Supreme Court because of her vote for Brett Kavanaugh, and this puts the issue more into hyper-drive,” Taylor said.

Maine House Speaker Sara Gideon, who has been ahead of Collins in polls and in fundraising, quickly cut a campaign ad saying Collins’s backing of McConnell, who controls the timetable for a confirmation vote, put voters’ rights at risk.

Meantime, Collins risks alienating the Trump supporters she needs in a state almost certain to go for Biden by opposing Trump’s pre-election confirmation push and refusing to say whether she’ll vote for Trump on Nov. 3.

Incumbent on Defensive

The court opening may be even worse news for Gardner, who has been badly trailing former Governor John Hickenlooper in the polls. He has aligned himself with the president, and quickly announced his support for going through with a confirmation vote. That may win over Trump supporters but not some of the independents necessary to win.

“He needs so much crossover support, and he doesn’t have a proven track record of doing that,” said Kyle Kondik, managing editor of Sabato’s Crystal Ball at the University of Virginia.

Gardner was already been on the defense after voting to repeal much of the Affordable Care Act. Now he’s in a position of voting for a high court nominee who could provide the fifth vote to undo that law -- including its popular protections for those with pre-existing conditions. The Supreme Court is set to hear arguments on the issue a week after Election Day. The Cook Political Report shifted its rating on Colorado to Lean Democrat from Tossup last week, citing in part the court dynamics.

Tipping-Point States

Three states seen as potential tipping points for Senate control -- and the presidency -- all feature incumbent Republicans who have been polling worse than Trump.

The confirmation fight may help Tillis, McSally and Ernst if it consolidates Trump’s supporters behind them, according to Kondik. Tillis and Ernst are on the Judiciary Committee that will conduct Barrett’s confirmation hearing.

But all three states have seen surges in Democratic fundraising and in support for Biden. The three incumbents each trailed their Democratic competitors in recent polls. A win for Biden in any of those states would almost certainly mean an ouster of the GOP senator.

The Democratic message in the three races is clear, illustrated by Democrat Cal Cunningham’s attack on Tillis for saying he’d vote for Trump’s pick before knowing who it was. He then tied the nomination to the GOP’s lawsuit to do away with the Affordable Care Act.

“We’re in a pandemic. Protecting the ACA has never been more important,” Cunningham tweeted.

Similar health care messages are being used by Democrats Mark Kelly against McSally in Arizona and Theresa Greenfield against Ernst in Iowa.

“The Republicans are on the defensive about health care, and the Democratic attacks get more potent because the Affordable Care Act is in danger of being gutted,” Kondik said. “That’s just the reality.”

Big Sky Battle

Daines has calculated that the court pick will help in a heavily Republican state that Trump won by 20 points four years ago. He quickly came out for confirming whoever Trump nominated.

The contest between Daines and his challenger, Democratic Governor Steve Bullock, has been mostly about Montana-focused issues, such as public land use and gun control, as well as health care and taxes. Both have said they would work with Trump on areas of common interest. That has left them essentially tied in a state where polling is scant.

Bullock has pointed out that Daines supported blocking Obama’s nominee in 2016 only to readily back Trump this year. But Montana isn’t necessarily as fertile ground as other states for making the court an issue, Kondik said. He noted that Democratic Senator Jon Tester won reelection in 2018 despite voting against Kavanaugh.

Taylor doesn’t see a repeat of 2018, when Republicans credited the fight over Kavanaugh with helping topple three Democratic senators in red states. “If Republicans are thinking that their Senate wins in 2018 were a referendum on the Kavanaugh vote, that’s a misreading of what happened, because that was an incredibly favorable map that already tilted toward Republicans,” she said, noting the GOP lost the House that year.

Taylor also doesn’t think the nomination will be enough to have most voters changing their focus from other key issues, including Trump’s handling of the pandemic.

“I still don’t think that most voters are going to forget that we still can’t go about normal daily life and over 200,000 people are dead,” she said.