DETROIT (AP) — A lawsuit has been filed challenging the 11-month gap between U.S. Rep. John Conyers' resignation and a special election.

Michael Gilmore claims the delay is unconstitutional. He filed the lawsuit Thursday in federal court on behalf of five voters in the 13th District. Gilmore is also a Democratic candidate who would like to win the seat.

Conyers, a Detroit Democrat, suddenly quit on Dec. 5. He cited health reasons, but the 88-year-old was also dogged by sexual harassment allegations.

Gov. Rick Snyder set the election for Nov. 6. The winner would serve until January 2019. There will be a separate race on the ballot for a regular two-year term.

Snyder said holding the special election on the day of the regular election will save money.