California Code, Elections Code - ELEC § 13110

The group of names of candidates for any partisan office, voter-nominated office, or nonpartisan office shall be the same on the ballots of all voters entitled to vote for candidates for that office, except that in partisan primary elections, the names of candidates for nomination to partisan office shall appear only on the ballots of the political party, the nomination of which they seek, and candidates for election to a political party committee shall appear only on the ballots of the political party for which the candidate seeks election.