DeSantis expressed support for using the U.S. military to combat drug cartels across the border.

"The president of the United States has to use all available powers as commander in chief to protect our country and the people," DeSantis said.

"When they are coming across, yes we are going to use lethal force," he continued -- a line he's used repeatedly throughout the campaign.

Activists have pushed back that his plan is inhumane and illegal.

-ABC News' Alexandra Hutzler

Martha MacCallum just asked about what to do about migrants already in the United States. In a July poll by The New York Times/Siena College, 39 percent of likely Republican voters say that they supported a “comprehensive immigration reform bill that provides a pathway to citizenship for all undocumented immigrants” in the United States, while 57 percent opposed such a bill. Support was weakest among Trump supporters (29 percent) compared with DeSantis supporters (48 percent) and voters who say they will vote for another candidate (50 percent).
-Analysis by FiveThirtyEight

While many candidates onstage have sparred with each other -- including Haley and Ramaswamy swapping sharp words on foreign policy -- Scott has yet to engage with any of the other candidates.

Much of his remarks have almost word for word repeated elements from his campaign stump speech. When asked about China, which he has addressed in other appearances, he pivoted to speaking about the U.S. border.

-ABC News’ Gabriella Abdul-Hakim and Oren Oppenheim

Asked to raise their hand if they would not increase aid to Ukraine, DeSantis did so, saying that "Europe needs to step up. They need to step up and do their job."

He argued: "I would have Europe pull their weight. ... Our support should be contingent on them doing it.

DeSantis -- who had received backlash from some other politicians for seemingly backtracking on support for Ukraine -- pivoted to say that he wasn’t going to send troops overseas but rather down to the Southern border.

-ABC News' Hannah Demissie and Will McDuffie

In 2016, Trump was the ultimate outsider candidate — he didn’t receive a single endorsement from a sitting senator, representative or governor until after he had already won New Hampshire, South Carolina and Nevada. This year, though, he already has a ton of elite support. According to the FiveThirtyEight endorsement tracker, he has 343 endorsement points — nearly eight times as many as DeSantis, who is in second place.

The 2016 race notwithstanding, endorsements have historically been very predictive of who eventually wins a party’s nomination. The candidate with the most FiveThirtyEight endorsement points on the day before the Iowa caucuses has won 11 of the last 17 Republican and Democratic primary fights without an incumbent president. And when that candidate has a dominant endorsement lead, they win even more often: Endorsement leaders who had collected more than 15 percent of the estimated available endorsement points before Iowa won nine times out of 10. And Trump already has 17 percent of all available endorsement points with five months left until Iowa.

-Analysis by Nathaniel Rakich of FiveThirtyEight