It took 15 minutes for the putative polling front-runner to get a word in, and DeSantis uses it to go after Trump on the debt and not showing up for the debate tonight. He even brought a prop -- a veto pen that he says he'll use to block "bloated spending" bills as president. But if he only gets off a few words every 15 minutes, this will be a long night for him.

—Jacob Rubashkin, 538 contributor

Christie goes after Republicans and Democrats for adding billions to the D.C., but he also takes a shot at Trump for not showing up to the debate. This is the first mention of the former president who is very likely to defeat all of these Republicans in the GOP primary.

—Analysis by Geoffrey Skelley of 538

While Ramaswamy clearly tried to differentiate himself from Scott on the question of unions, Pence glossed over his primary challengers and shifted directly to the general election, calling for repealing the Green New Deal and criticizing Biden.
— Analysis by Leah Askarinam of 538

According to a September poll by ABC News and The Washington Post, 74 percent of Republicans said they would blame Biden and the Democrats in Congress if the government were to shut down. Just 5 percent said they would blame Republicans in Congress, and 16 percent said they would blame both equally. Five percent didn’t have an opinion or wouldn’t blame either.
—Analysis by 538

Outside of the Trump-critical wing of the Republican primary — featuring Christie and Hutchinson, with major appearances by Pence — most of the presidential field has tip-toed around Trump, careful not to attract his ire. But in the last couple weeks, some candidates have started taking on Trump more directly, jeopardizing their prospects as his running mate.

Trump was already unlikely to name a challenger as his VP pick. Of the 19 unique Democratic and Republican presidential nominees since 1972, only four selected a running mate who had run against them in the same year’s primary. And Trump is even more prickly about loyalty than his recent predecessors.

Last week, we analyzed the tweets of the six highest-polling Republican candidates (other than Trump) in 538’s national polling average. Until recently, DeSantis had hardly acknowledged the former president, mentioning Trump just once since Jan. 6, 2021. But that changed last week, when DeSantis published three critical tweets about Trump. Scott, meanwhile, has largely kept his social media tone neutral toward Trump, but we did see a rare direct criticism on the stump last week, when he said Trump’s suggestion that he’d seek a compromise on federal abortion legislation was the wrong approach. Haley’s tone toward Trump shifted earlier this summer, from cautious to directly critical.

Tonight could tell us whether these recent instances of criticism are the beginnings of a new trend in which the GOP field actually tries to topple the front-runner.

—Analysis by Leah Askarinam of 538