Likely Republican voters are pretty split on "sending U.S. military forces to Mexico to fight drug cartels," according to our pre-debate 538/Washington Post/Ipsos poll. 44 percent support the proposed policy, compared with 46 percent who oppose.

—Analysis by Holly Fuong of 538

Some early moments in this debate have involved significant cross-talk and interruptions. Burgum's main two comments so far both came via him jumping in to speak without having been asked a question, which is something a low-polling candidate on the periphery of the stage (and race) might as well do with little to lose. Unlike in the first debate, there hasn't been as much of a push by the moderators to give a short rebuttal opportunity to candidates who were mentioned by another candidate, although multiple candidates have asked for that already.

—Analysis by Geoffrey Skelley of 538

The Trump administration built 52 miles of new primary border barriers — the first impediment people encounter if they’re trying to cross the southern border with Mexico, that can block access either for people on foot or for vehicles — where there were none before.

The administration built 458 total miles of primary and secondary border barriers, U.S. Customs and Border Protection data shows. The majority were replacements of smaller, dilapidated barriers.

The U.S.-Mexico border stretches for 2,000 miles across four states and a variety of terrain.
-Analysis by Aaron Sharockman, PolitiFact

Christie was just asked about his position on a pathway to citizenship for undocumented immigrants. 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 538

When debate moderators asked the 2024 GOP candidates about the impending government shutdown, some – including Trump’s closest opponent DeSantis – pivoted to blame the former president and current President Biden for the logjam.

Both men also called out Trump for his absence on stage, noting that he should be answering for himself as the shutdown looms.

"People in Washington are shutting down the American dream with their reckless behavior,” DeSantis said.

“And you know who else is missing an action? Donald Trump is missing an action. He should be on this stage tonight. He owes it to you to defend his record where they added 7.8 trillion to the debt that set the stage for the inflation that we have.”

Chris Christie – one of Trump’s staunchest critics – also admonished the former president.

“If the government shuts down, should voters blame populace Republicans? Very simply everybody who's in Washington, D.C.,” said Christie.

“And let's be honest about this with the voters. You know, during the Trump administration, they added $7 trillion — $7 trillion in national debt. And now the Biden administration has put another 5 trillion on and counting.”

“Donald Trump– he hides behind the walls of his golf clubs, and won't show up here to answer questions like all the rest of us are up here. He puts 7 trillion on the debt. He should be in this room to answer those questions for the people you talk about who are suffering,” Christie said.

–ABC News’ Isabella Murray