Gov. Ron DeSantis of Florida began the race for the Republican nomination with high expectations and a clear argument: that he was a political fighter with a solid record of conservative achievements in his state. Now, he appears to be in a downward spiral. Shane Goldmacher, a national political reporter for The Times, explains why the DeSantis campaign is stumbling so badly. Guest: Shane Goldmacher, a national political reporter for The New York Times.