Here’s what you need to know:
- Two G.O.P. Senate primaries offer — what else? — a test of loyalty to Trump.
- President Trump is suddenly a big supporter of mail-in voting — in Florida.
- Michigan’s primary election sees a surge in absentee voting.
- Rashida Tlaib, a fierce Trump critic, faces a stiff Democratic challenge in Michigan.
- Why Kris Kobach’s run in Kansas has Republicans nervous.
- In St. Louis, a progressive challenger will try again to unseat a longtime congressman.
- Joe Arpaio is testing the patience of Arizona Republicans.