Four states hold primaries Tuesday: Alabama, Arkansas, Georgia and Texas, where there are runoff races following an election on March 1.
In Alabama, GOP incumbent Gov. Kay Ivey faces primary challengers. And Katie Britt, former head of the Business Council of Alabama, Army veteran Mike Durant and Rep. Mo Brooks are all seeking to replace GOP Sen. Richard Shelby. At one time Brooks had the endorsement of Donald Trump, though the former president later withdrew that support.
Polls close at 8 p.m. ET.