After each debate, we are releasing numbers from new polling with Ipsos and The Washington Post that show who debate viewers thought won the debate. But since this is the second debate of the campaign, we have the benefit of getting a month’s worth of new polls to average since the first debate. Overall, the picture remains largely the same — but there are some minor changes in the race for second place.

538’s latest national polling average has Trump at 54 percent of the vote among likely Republican primary voters nationwide. On the eve of the last debate in late August, Trump was polling at 52 percent. DeSantis is in second at 14 percent; he was at 15 percent heading into the last debate. Following him are: Ramaswamy, who rose to 10 percent following the last debate but has since settled at 6 percent; Haley at 6 percent (up from 3); Pence at 5 percent (up from 4); Christie and Scott at 3 percent each; and everyone else at 1 percent or below.

—Analysis by G. Elliott Morris of 538

538’s Galen Druke traveled to Simi Valley, California — home of the Ronald Reagan Presidential Library and tonight’s debate — to explore why an area that was once a Republican bastion voted for President Biden in 2020 and whether Republicans can win it back.

The second debate stage will look mostly like the first, as seven of the eight candidates who took part in the initial August debate qualified for tonight’s event. And just like the first debate, front-runner Trump has decided to skip the event, despite having the polls and donors to make it. To qualify, the RNC mandated that candidates have at least 3 percent support in two national polls, or at least 3 percent in one nationwide survey and two polls from separate early states, based on polls conducted since Aug. 1 that met the RNC’s criteria for inclusion. Candidates also had to attract at least 50,000 unique contributors, with at least 200 from 20 different states or territories.

The RNC raised the polling and donor standards for the second debate, which slightly winnowed the list of participants. The new rules raised the level of support candidates needed in qualifying polls from 1 percent to 3 percent, and the number of unique donors from 40,000 to 50,000. Six of the seven qualifying candidates had little trouble meeting these polling and donor thresholds. However, although Burgum had enough donors, he struggled to poll well enough nationally to qualify. It took until the Saturday before the debate for him to get the national poll at 3 percent he needed. Meanwhile, former Texas Rep. Will Hurd and former Arkansas Gov. Asa Hutchinson came up short of qualification, as Hurd lacked sufficient polls and only got to 50,000 donors on Monday, while Hutchinson didn’t have enough qualifying polls or donors.

—Analysis by Geoffrey Skelley of 538

It’s time again for another Republican presidential debate — with another conspicuous absence and a slightly smaller stage.

Tonight’s debate will feature seven candidates, down from eight last month. Former President Donald Trump, who has a 41-percentage-point lead in 538’s national polling average, will again not be among them, as he has decided to skip at least the first two debates. Instead, we will hear from Florida Gov. Ron DeSantis; entrepreneur Vivek Ramaswamy; former Vice President Mike Pence; South Carolina Sen. Tim Scott; former U.N. Ambassador Nikki Haley; former New Jersey Gov. Chris Christie; and North Dakota Gov. Doug Burgum.

Ramaswamy, DeSantis and Haley impressed Republican debate watchers last month, but within weeks, it became apparent that the debate did not significantly change the contours of the race. So this go-around, we’ll be watching to see whether any candidate takes a different approach to Trump (or the lack thereof) on the stage tonight. How will candidates make the case that they are the best alternative to Trump without having him there as a direct contrast? What issues will they try to differentiate themselves on?

The debate begins at 9 p.m. Eastern on Fox Business, but you’ll be hearing here from the crew at 538 and contributors from ABC News and PolitiFact throughout the night. Leading up to the debate, we’ll run through the state of the race so far. Once the event starts, we’ll make sure we’re addressing everything happening on stage, including what issues the candidates talk about, whom they attack, how they position themselves and what Americans think. Thanks for joining us.

—Analysis by Maya Sweedler of 538

I'm at the Reagan Library in Simi Valley, California, for the Republican debate tonight and so far it's been a Democrat who's caused the biggest stir in the spin room. California Gov. Gavin Newsom came through for an interview with Univision and a rather lengthy gaggle with the national press corps. He defended his decision to debate DeSantis later this year, defended his presence at a Republican debate in the first place and he answered a question from yours truly.

I asked him about one of the issues that Biden is currently faring worst with the American public on: immigration, and specifically border security. Newsom told me he supports Biden's plan on this issue, but that: “The one thing I would add to it, not what’s wrong with it, is we need to do more on the asylum space as it relates to how the asylum system is being gamed and that is legitimate.”