Louisiana is a reliable Republican state in presidential elections. There is a statewide race for U.S. Senate this year, with Republican incumbent Bill Cassidy running for reelection. The state has six congressional districts. Louisiana presidential primaries are closed; only those registered with a party can vote. For congressional offices, Louisiana holds an open primary on Election Day in November, with all candidates on the same ballot. If no candidate gets more than 50% support, the top two candidates go to a runoff election on Dec. 5, regardless of party.