Voter Pre-Registration Deadline. The deadline to pre-register to vote for the primary election is 5 p.m. This applies to registration in person (including registration at driver’s license stations or agencies) or by mail. Exceptions: Mailed registration forms postmarked on or before the worry-free postmark date, are considered on time even if they are received after 5 p.m. today.After today, a person may register to vote at the auditor’s office or at a satellite absentee voting station and vote an absentee ballot. The process is the same as for registering to vote on election day.