Haley finally gets a question on foreign policy, a strong suit for the former U.N. Ambassador. She defends American support for Ukraine and ties it to the fight against China. But while the moderators teed her up to attack DeSantis, she instead pivots to Ramaswamy. She's pretty fiery in her back-and-forth with him, saying he has no foreign policy experience "and it shows."
-Analysis from Jacob Rubashkin, Inside Elections

On Russia's invasion of Ukraine, Christie referenced his recent trip to the war-torn country and said that he "wanted to see for myself what [Russian President] Vladimir Putin's army was doing to the free Ukrainian people."

"They have gouged out people's eyes, cut off their ears and shot people in the back of the head," Christie said of the brutality he saw.

"This is the Vladimir Putin who Donald Trump called 'brilliant' and a 'genius,'" he continued. "If we don't stand up against this type of autocratic killing, we will be next."

-ABC News' Meredith Deliso

Born in 1985 and only 38, Ramaswamy may be the only candidate on stage who was too young to remember the Cold War. The USSR dissolved when he was 6.
-Analysis by Monica Potts of FiveThirtyEight

The debate over Ukraine is a window into the intraparty battle between its previously more dominant neoconservative wing that lost credibility during and after the George W. Bush years and the comparably isolationist wing that's gained ground with Trump's time in office. Ramaswamy, as an avatar for the New Right, specifically name-checked the Iraq War, saying the Ukraine conflict could lead to American intervention. By comparison, Pence and Haley, more traditional conservatives who have foreign policy experience from their time as vice president and U.N. ambassador, respectively, were especially vocal in defending U.S. support for Ukraine.-Analysis by Geoffrey Skelley of FiveThirtyEight

As Republican candidates gear up for the debate, many have specific rituals they’ll be doing in preparation.

A campaign adviser for Haley said she will be listening to music, “lots and lots of music: Joan Jett, Queen, Def Leppard and [the] Go-Gos, to name a few.”

DeSantis has spent today with his wife, Casey, and their three children, though a campaign spokesman offered few details about how the family has spent their time.

Hutchinson posted a photo of himself preparing with notepad and laptop in hand.

“Some last minute studying and prep for tomorrow! It’s important to show up and be ready to answer the tough questions, you deserve nothing less than a leader ready to lead on day one,” Hutchinson captioned the photo online.

Pence will plan to spend time in prayer before the debate, while Scott took a tour of the debate stage, which he posted a video of, along with encouragements from his family, to X, formerly known as Twitter.

Others prepared physically, earlier this week.

Ramaswamy posted videos to X of himself playing tennis and him and his wife doing floor exercises in a gym throughout the lead-up week.

Burgum was playing a stress-relieving pickup game of basketball on the eve of the debate, according to a campaign press secretary, when he sustained an Achilles injury that called into question his ability to participate in the event.

He will be participating, albeit on crutches, per a photo posted to his X account.

-ABC News’ Gabriella Abdul-Hakim, Libby Cathey, Abby Cruz, Will McDuffie and Olivia Osteen