Loophole could allow double voting in California Primary Election Contra Costa County - There is a loophole that potentially allows California voters to cast two ballots and some local elections officials say that they are powerless to stop it. Hundreds of voters have attempted to vote more than once because the state’s automated system sends a new vote-by-mail ballot if personal information or party preference changes. https://www.ktvu.com/news/loophole-could-allow-double-voting-in-california-primary-election