DeSantis is trying a bit there to be the adult in the room, which was effective for him last debate when he derailed a question about climate change, but isn't as effective this time around.

-Jacob Rubashkin, 538 Contributor

Ramaswamy brings up one of his key stump speech issues, ending "birthright" citizenship for people who are born on American soil. It's one of the ideas Trump championed in his campaign and earlier presidency — a bit of showing his hand here as he tacks to be the default Trump replacement in the case that he ends up dropping out of the race.

— Analysis by G. Elliott Morris of 538

Republican primary voters are further to the right on many immigration issues than the general electorate. They support building a border wall, increasing border patrols, and defunding sanctuary cities. In 2020, the last presidential election year, 62 percent opposed a path to citizenship for undocumented immigrations. Ending birthright citizenship, as Ramaswamy says he wants to do, is even more extreme. Candidates tonight are trying to woo those voters tonight with their stances on immigration, but they risk boxing themselves into unpopular opinions should they make it to the general election.
— Analysis by Monica Potts of 538

DeSantis gets a question on China and says he wants a totally new approach to that country. He says that he wants to ban the Chinese Communist Party from buying land anywhere in America, and also says he doesn't want them in our universities. It wasn't clear if he was talking about all Chinese students, or just the Confucius Institutes he mentioned right after.

—Jacob Rubashkin, 538 contributor

At several points during the second hour of the debate, it got particularly heated between former South Carolina Gov. Nikki Haley and someone she appointed to the U.S. Senate in 2013: Tim Scott.

Haley first went after Scott for not completing what he touted as his economic policy accomplishments.

“I appreciate him. We've known each other a long time. But he's been there 12 years and he hasn't done any of that. He has, they've only given four audits on time,” she said.

Then came a heated back-and-forth before Haley repeated, “Twelve years, where have you been? ... Bring it, Tim.”

The two also fought over Haley’s gas tax in South Carolina.

“​​I would love to finish my conversation with Nikki as it relates to the job that needs to get done. Nikki offered a 10-cent gas tax increase in South Carolina. Talk about someone who has never seen a federal dollar,” Scott said.

Haley then told Scott to do his homework regarding the spending and gas tax in South Carolina. He responded, “just go to YouTube.”

Haley ended the exchange by telling Scott that he was “scrapping right now” (as in scrambling).

“You are scrapping right now, you are scrapping. You know, I fought taxes, I cut taxes, I took care of South Carolina and you know it.”

They then got into a rift over a set of over $50,000 customized curtains for the State Department in the official residence of the ambassador to the United Nations. Haley was the first to live in the new residence.

–ABC News’ Abby Cruz, Gabriella Abdul-Hakim and Isabella Murray