We've been here before: Republican presidential hopefuls take the debate stage - without their party's overwhelming front-runner.
But for this fourth primary debate, the field is smaller than ever, with just four candidates meeting the Republican National Committee's criteria to participate on stage in Tuscaloosa, Ala. There's also just over a month from the Iowa Caucuses, so time is getting short to win over undecided voters.
The participants will be former New Jersey Gov. Chris Christie, Florida Gov. Ron DeSantis, former United Nations Ambassador Nikki Haley and businessman Vivek Ramaswamy. As before, former President Donald Trump won't be there.
Here's a guide to what to watch for.
What's at stake
After missing last month's debate and again failing to qualify for this one, North Dakota Gov. Doug Burgum dropped out of the race this week. South Carolina Sen. Tim Scott, who was in the debate last month, also recently dropped out.
As the field keeps getting smaller, the remaining candidates will have more time to try to distinguish themselves and demonstrate they have a viable path to the nomination, despite Trump's dominance.
Republican pollster Jon McHenry of North Star Opinion Research believes there's still a narrow opening for an alternative, "as much as Donald Trump is trying to force it closed and lock it."
But, debate performance is crucial at this stage.
"Because there's only four, and they all get more airtime, it puts a premium on actually being knowledgeable about these issues," McHenry explained.
McHenry thinks it's a make-or-break moment, particularly for DeSantis, who'd once been seen as the most likely Republican hopeful to take on Trump. But McHenry points to a recent shakeup at a pro-DeSantis super PAC, and the fact that Haley seems to have stepped into that role based on polling and support from donors like the Koch network.
Issues to watch
- Foreign policy: With the resumption of fighting between Israel and Hamas, and President Biden's message to Congress that he needs more funding for Ukraine, international affairs are likely to take up significant time. Republicans are in lockstep on support for Israel but Ukraine funding is more divisive.
- The nation continues to face the ever-looming possibility of government shutdown if House Republicans can't agree on a budget.
- Abortion remains a challenging issue for Republicans in a post-Roe v. Wade environment. All of the primary candidates support some restrictions, but they've differed on questions like whether they'd support a hypothetical national ban and just how restrictive they want to be. Christie and Haley recently sparred over the issue after Haley said at an event hosted by an Iowa evangelical group that she would've signed a six-week abortion ban as South Carolina's governor. Christie went after Haley, saying he would not sign such a ban.
- Trump's legal troubles: Trump's impending trials present an opportunity to remind Republican voters that he is vulnerable. But each candidate has to make a calculation about how much they want to go after their party's popular frontrunner.
Once again, no Trump
For the three previous debates, Trump has held some kind of counterprogramming event, such as a rally or major interview. This time, in what looks to be another sign of just how confident he's feeling in this primary, Trump is attending a private fundraiser in Florida - as Florida's governor, Ron DeSantis, debates the rest of Trump's challengers in Alabama.
