Are you registered to vote? Tuesday July 17 at 4:30 p.m. is the deadline to register in Jefferson County for the primary election August 7th. If you are already registered you don't have to re-register. If you're not sure, you can check to see if you are registered by visiting the website VoteKS.org. You can also view a sample ballot for your voting precinct from this site as well as get an advance ballot application and find out about the new Voter ID law.