Noting the above, California state and federal offices go through a "unitary" primary election in which
all candidates in a given race regardless of party affiliation are on a single primary ballot. The top two vote getters advance to the general election.
Meaning that in a general election, the two candidates might well (and have been) be from the same party. Funky system, but rather unique to California and I will refrain from expressing any opinion thereto.
https://ballotpedia.org/Primary_elec...lifornia,_2018
June 5, 2018 is the primary date.
So, unlike Texas and pert near most other states, the parties don't run the balloting.
Not sure about "party questions" such as the GOP ballots had in the Texas primary this week.