Highlights from the Republican presidential primary debate at the Ronald Reagan Presidential Library in Simi Valley, Calif.

From right: North Dakota governor Doug Burgum, former New Jersey governor Chris Christie, former South Carolina governor Nikki Haley, Florida governor Ron DeSantis, Vivek Ramaswamy, Sen. Tim Scott (R., S.C.), and former vice president Mike Pence pose at the second Republican candidates’ debate at the Ronald Reagan Presidential Library in Simi Valley, Calif., September 27, 2023.

David Swanson/Reuters