Sen. Richard Shelby of Alabama announced Monday that he won’t run for re-election—the latest in a string of GOP senators to bow out of 2022. Rob Portman of Ohio, Pat Toomey of Pennsylvania, and Richard Burr of North Carolina previously announced they are giving up their seats in the Senate, which is split 50-50 between Democrats and Republicans. Shelby, 86, has been in Congress for 42 years and has chaired the Appropriations, Rules, Banking, and Intelligence committees over the course of his career.

According to Politico, the field of those who might run for the seat includes Rep. Mo Brooks and Rep. Gary Palmer.