Illinois Primary Election Absentee Ballot Return Deadline (Postmarked On or Before Election Day and Received by) March 31 Indiana Primary Election Voter Registration Deadline (In-Person Request by) April 6 Indiana Primary Election Voter Registration Deadline (Postmarked by) April 6 Ohio Primary Election Voter Registration Deadline (Postmarked by) April 6 Ohio Primary Election Voter Registration Deadline (Received by) April 6
