California State Assembly member Pete Wilson and former San Diego City Attorney Ed Butler received the most votes in the primary and advanced to the runoff.

In October 1970, prior to the beginning of the campaign, incumbent Mayor Frank Curran and several other City officials were indicted for allegedly taking bribes from the Yellow Cab Company.

Five of Curran's challengers had previous experience in elected office, including California State Assembly member Pete Wilson, former San Diego City Attorney Ed Bulter, San Diego Board of Supervisors member Jack Walsh, former member of the Assembly and the San Diego City Council Tom Hom, and city council member Mike Schaefer.

The remaining eight challengers were political outsiders running for their first elective office.

[6] Because no candidate received a majority of the vote, the top two vote-getters, Wilson and Butler, advanced to the runoff election scheduled for November 2, 1971.