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

This is False.

Pence has used this 90 percent drop statistic many times, but has never explained where it comes from.

When the COVID-19 pandemic started, immigration drastically dropped worldwide as governments enacted policies limiting people’s movement. In the U.S., Trump instituted Title 42, a public health policy that authorized the Border Patrol to immediately return most immigrants back to Mexico. The increased use of this policy decreased the use of other programs, including "Remain in Mexico."

U.S. Customs and Border Protection during the pandemic also adopted a new way of reporting migrant encounters. Before the pandemic, it only reported enforcement actions under immigration law; its data during the pandemic includes actions taken under both immigration law and the public health policy. Therefore, 2020 data isn’t entirely comparable to pre-pandemic numbers.

Accounting for challenges in data comparisons, our review found an increase of 300 percent in illegal immigration from Trump’s first full month in office, February 2017, to his last full month, December 2020.

One way to get close to Pence’s alleged 90 percent decrease in illegal immigration is by comparing data from May 2019, the month during the administration that had the highest apprehensions, to April 2020, the month with the lowest enforcement actions in calendar year 2020.

But that’s a severely cherry-picked time period.
-Analysis by Aaron Sharockman, PolitiFact