Final answer:
California has a top-two primary system where all candidates, regardless of party affiliation, compete against each other in the primary election. The top two candidates move on to the general election.
Step-by-step explanation:
California has a top-two primary system for state-level office nominations, including the nomination of U.S. Senators and House members. In this system, all candidates, regardless of party affiliation, compete against each other in the primary election. The top two candidates who receive the most votes move on to the general election, even if they are from the same party. This system allows for more competition and can result in candidates from different parties or the same party competing in the general election.