Just as in Chicago, the idea of having elections in a hardcore democrat stronghold like L.A. is meaningless after the dems’ primary. GOPers who attempt to run for high office in those cities are wasting their time.
There is no "Democratic primary" for Mayor of LA. There is one election, in which all candidates are on the ballot regardless of party affiliation; if no one wins 50%+1, there is a run-off between the top two candidates.