The Times reporter Astead W. Herndon and the team are back for a new season of “The Run-Up” and they’re looking ahead to the 2024 presidential election, which in many ways has already begun. In this first episode, Astead heads to California for the Republican National Committee’s winter meeting to explore the tangled lines and scrambled allegiances that animated the effort to unseat Ronna McDaniel, the chair of the R.N.C.