New Jersey New Jersey Election Voter Registration Deadline for the Primary Election May 20 New Jersey New Jersey Election Mailing of Sample Ballots for Primary Election May 28 New Jersey New Jersey Election Deadline to apply for a Mail-In Ballot by Mail for Primary Election June 3 New Jersey New Jersey Election Early Voting Period - Primary Election - Begins June 3 New Jersey New Jersey Election Early Voting Period - Primary Election - Ends June 8