The party-based rules for the 2024 primaries make for news.  Both parties will caucus in Iowa on January 15.  The DEMs will not announce their results until after primaries in SC  and NV, February 3 and February 6, respectively.  The NH primary will fall on January 23.   DEMs seek to avoid primaries in largely-white population states to have a disproportionate impact on candidates.

The nature of primaries, by state, is shown below.