Republicans are meeting for their second presidential debate Wednesday as his top rivals seek to blunt the momentum of Donald Trump, who is so confident of cruising through the party’s primary that he again won’t share a stage with them.

Seven GOP candidates will be at the Ronald Reagan Presidential Library for an event hosted by Fox Business Network. Trump will be in Michigan, delivering a prime-time speech attempting to capitalize on the Auto Workers Union strike and trying to appeal to rank-and-file union members in a key state for the general election.

The debate comes at a critical moment in the GOP campaign, with less than four months before the Iowa caucuses formally launch the presidential nomination process. For now, Trump is dominating the field even as he faces a range of vulnerabilities, including four criminal indictments that raise the prospect of decades in prison. His rivals are running out of time to dent his lead, which is building a sense of urgency among some to more directly take on the former president before an audience of millions.

“This is not a nomination that’s going to fall in your lap. You have to go and beat the other candidates and one of those happens to be Donald Trump,” said Kevin Madden, a Republican strategist and veteran of Mitt Romney’s 2008 and 2012 presidential campaigns. “This debate, it’ll be interesting to see whether or not folks realize that the sand is going through the hourglass pretty quickly right now.”

The former president also skipped the first debate last month in Milwaukee, where the participants laid into one another while mostly avoiding attacks on Trump. Nearly 13 million people tuned in anyway.

Nikki Haley, the former South Carolina governor and United Nations ambassador, drew larger crowds and new interest after her first debate performance in which she attacked entrepreneur Vivek Ramaswamy on foreign policy and pointed out that she was the only woman in the field.

Her team has raised expectations even higher going into Wednesday night, telling donors in a recent pitch that they are “ready to capitalize on the momentum after Nikki walks off stage.”

“As more voters across America tune in to watch the second debate, it’ll be a great opportunity to bring even more supporters into the fold,” Haley’s campaign manager, Betsy Ankney, wrote in her email.

Also hoping for a big night is Florida Gov. Ron DeSantis, who will be at center stage despite recent struggles to emerge as the field’s top Trump alternative. His campaign announced that he also saw a jump in fundraising after the first debate, but a strong performance on Wednesday will likely be necessary to replicate that.

“It’s too late for just a fine performance,” said Christine Matthews, a national Republican pollster. “DeSantis has gone from leading alternative to Trump to just one of the pack of challengers and he will be under pressure to perform.”

Former Vice President Mike Pence, South Carolina Sen. Tim Scott and Ramaswamy are similarly looking for breakout moments. Ramaswamy seized the spotlight frequently in Milwaukee, but was criticized by many candidates who sought to expose his lack of political experience.

Also on stage will be North Dakota Gov. Doug Burgum and Chris Christie, the former New Jersey governor, who has built his White House bid around slamming Trump.

Former Arkansas Gov. Asa Hutchinson failed to qualify after making the first debate. Hutchinson’s campaign says he’ll also go to Michigan to hold a press conference criticizing Trump.

Ahead of the debate, many participants were meeting with top supporters, donors and reporters to make the case that they are best positioned going forward.

Reed Galen, co-founder of the Lincoln Project, an organization founded by conservatives who oppose Trump, said that while he still believes the former president will ultimately be the Republican nominee in 2024, Wednesday’s debate offers a chance for others to make up ground.

“There are opportunities in the offing because Trump is taking this for granted,” Galen said.

The site is symbolic given that Reagan has long been a Republican icon whose words and key moments still shape GOP politics today. But in addition to fighting with the Reagan library’s leaders, Trump has reshaped the party and pushed away from traditional GOP policy positions — including a muscular foreign policy and opposition to Moscow.

While Reagan is remembered for going to a divided Berlin and calling on Soviet leader Mikhail Gorbachev to “tear down this wall,” Trump has often sympathized with Russian President Vladimir Putin and recently said, “I was the apple of his eye.”

Pence, in a recent speech, called on conservatives to reject Trump’s “siren song of populism.” But Ramaswamy attacked Pence in the first debate by declaring “it’s not morning in America” — a reversal of Reagan’s famous 1984 campaign slogan — and saying Republicans following Reagan were out of step with a Trump-dominated party.

“The sad thing is, the irony — and I don’t know how many people there will get it — is that Ronald Reagan could not get the Republican nomination today,” said former Republican New Jersey Gov. Christine Todd Whitman, who is now teaming with Democratic voices to promote the centrist Forward Party. “He’s not far enough out there.”