Most Mississippi cities elect mayors this year, and party primaries Tuesday will narrow the fields of candidates.
Some of the toughest primaries are in Jackson, Vicksburg, Clarksdale and Madison.
Primary runoffs are May 21. The general election is June 4, with mayoral terms beginning July 1.
Jackson Mayor Harvey Johnson Jr. is seeking a fourth term. He faces nine other Democrats. Three independents are running.
First-term Vicksburg Mayor Paul Winfield is challenged by Rep. George Flaggs, businesswoman Linda Fondren and three other Democrats. One independent is running.
In Clarksdale, Rep. Chuck Espy faces two Democrats, including Bill Luckett, who ran for governor in 2011. One Republican and one independent are running.
Longtime Madison Mayor Mary Hawkins Butler is challenged in the Republican primary by John Bell Crosby, a county supervisor.