Former President Donald Trump and Florida Gov. Ron DeSantis dug in this weekend for what is expected to be a bitter and personal race between the two for the 2024 GOP presidential nomination. Mr. Trump revved up supporters Saturday at the Conservative Political Action Conference outside Washington—an event Mr. DeSantis skipped—while the governor appeared before Republican groups in Texas and gave a speech Sunday afternoon at the Ronald Reagan Presidential Library in California. The two will then descend on Iowa, which holds the first GOP nominating contest. Mr. Trump has already launched his campaign; Mr. DeSantis, the front-runner among the...