Illinois will hold a special election on September 10 to fill the vacant U.S. House seat in the 18th district. See this story. The primary will be July 7. Thanks to Thomas Jones for the link.

Here are details from the State Board of Elections. Democrats need 626 signatures by April 20, and Republicans need 1,014 signatures by the same date. Nominees of unqualified parties, and independent candidates, need 12,602 signatures, due June 25.

The United States government had sued Illinois over the dates involving this special election. Originally the state was going to have the primary on June 8 and the special election itself on July 24. The case was United States v State of Illinois, northern district, 1:15cv-2997. The state gave in and did not contest the lawsuit, and agreed to provide more time between the primary and the election so that overseas absentee ballots would have more time to receive and return their ballots.