Haley going after Ramaswamy was a recurring theme in the first debate. They were the standout candidates in our polling last time and there was a lot of speculation about Ramaswamy moving up in the polls — perhaps even surpassing DeSantis. But since August, Ramaswamy has actually lost support, to the point where Haley passed him in our polling average today. It makes sense that they're trading blows again; this seems to be a successful strategy for Haley, and Ramaswamy can't help but take the bait.
-Analysis by G. Elliott Morris of 538

The candidates are discussing support for Ukraine. About half (49 percent) of Republicans and Republican-leaning independents say that vital U.S. interests are not really at stake in the war in Ukraine, according to an August Echelon Insights survey. Thirty-seven percent disagree, saying that if Russia wins, vital U.S. interests and values are threatened. Fourteen percent are unsure.
—Analysis by 538

For those keeping score at hope, Christie, Pence, Scott and now Haley have all gotten into shouting matches with Ramaswamy at these debates.

—Analysis by Nathaniel Rakich of 538

DeSantis finally gets a little momentum. His "they don't care" repetition is the most impassioned he's been all night (or in either debate). But whatever applause he might have got was cut short the conversation moving on a discussion about NATO and another Scott/Ramaswamy spat.
-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