Adding onto Nathaniel's Google search comment ... debates can serve as a great introduction to some of the lesser-known candidates. Ramaswamy is probably tonight’s big winner in making a name for himself: 59 percent of voters had no opinion or had never heard of Ramaswamy before tonight, according to a favorability question in our pre-debate FiveThirtyEight/Washington Post/Ipsos poll. That’s likely changed after all of the talking he’s done on stage — and we’ll be tracking whether that’s a good or bad thing. Check back in at FiveThirtyEight tomorrow afternoon for our post-debate analysis.
-Analysis by Holly Fuong of FiveThirtyEight

Pence was pressed by moderators if presidents should have to pass a mental and physical test to serve, invoking President Joe Biden's age.

Pence, who is 64, initially joked that "it might be a good idea to have everybody in Washington" pass one.

He then took a serious tone, saying, "No, the American people can make those judgments."

He appeared to take a swipe at Ramaswamy, the youngest candidate on stage, stating the nation doesn't need a president who is too young either.

-ABC News' Alexandra Hutzler

In the front-runner's absence, many of us here at FiveThirtyEight suspected (in part because of some leaked debate memos) that the former president would loom large over the proceedings, with candidates taking shots at him whenever possible. That hasn't really happened tonight, though! What do you make of it?

-Analysis by Maya Sweedler of FiveThirtyEight

Ramaswamy has been far and away the most Googled candidate during the debate tonight. He’s received three times as much search interest as DeSantis or Haley. Now, I’m not sure what that means for his chances — Google searches aren’t votes, and people might just be curious to learn more about him. But I think it does reflect that he has been the story of this debate so far. Whether that’s a good story for him or a bad story is still TBD.
-Analysis by Nathaniel Rakich of FiveThirtyEight

The 2024 presidential election has been underway for months, but with tonight’s first Republican primary debate in Milwaukee, we’re kicking off a new phase of the campaign. In these final five months before voting begins, we’re going to have monthly debates, dashes through Iowa, big-money fundraisers — and probably a culling of the field.

Tonight’s debate will feature eight candidates. Front-runner Donald Trump, who has a 37-percentage-point lead in FiveThirtyEight’s national polling average, will not be among them, as he has opted to skip the debate. Instead, we will hear from Florida Gov. Ron DeSantis; entrepreneur Vivek Ramaswamy; former Vice President Mike Pence; Sen. Tim Scott; former U.N. Ambassador Nikki Haley; former Arkansas Gov. Asa Hutchinson; North Dakota Gov. Doug Burgum; and former New Jersey Gov. Chris Christie.

There are a few threads and tensions we’re going to be watching tonight. First, in the absence of Trump, will his challengers’ attempts to position themselves as a more favorable option fall flat? How will candidates make their case for being a better alternative to Trump without having the contrast on stage beside them? Secondly, what sort of friction will we see between the anti-Trump candidates and those running on more similar ideas or rhetoric?

We’ll keep an eye on all this and more. You’ll be hearing from the crew at FiveThirtyEight and ABC News — as well as some new friends at PolitiFact — throughout the night. The Fox News-hosted debate begins at 9 p.m. Eastern, and we have some colleagues on the ground in Milwaukee who will ensure you’re going in with everything you need to know.

Thanks for joining us. Stay tuned as we update the blog with real-time analysis, charts, thoughts, questions, ideas, idle fancies and more. Leading up until the debate starts, we’ll run through the state of the race so far. Once the debate starts, we’ll make sure we’re addressing everything happening on stage, including what issues the candidates talk about, who they attack, how they position themselves and what Americans think.

-Analysis by Maya Sweedler of FiveThirtyEight