Reviewing Precinct Returns from the San Diego Mayoral Election

Vince Vasquez Vince Vasquez



The race to become mayor of the City of San Diego has narrowed down to two finalists. In this policy brief the National University System Institute for Policy Research (NUSIPR) analyzed newly released electoral data from the San Diego County Registrar of Voters’ office using GIS software.


The June mayoral primary was a partisan election. Interstate 8 continues to delineate a partisan divide in San Diego, which weighed heavily in the electoral outcome. GIS maps show that Republican DeMaio earned most of his votes in older, more conservative neighborhoods north of Interestate 8, while Democrat Filner won the lion’s share of votes among the younger, more diverse and liberal enclaves south of 8. Both candidates are likely to target low-propensity partisan voters that did not turn out for the June election, to shore up their base early in the fall election.

Support for Bonnie Dumanis and Nathan Fletcher lacked a geographic base. NUSIPR found that District Attorney Bonnie Dumanis and State Assemblyman Nathan Fletcher won only a handful of precincts outright, even when combining their votes. GIS mapping shows that there was no clear territory where either candidate earned deep voter support. Generally, Dumanis and Fletcher did best in parts of Carmel Valley, Point Loma, and Mission Valley. However, in only 9 precincts (out of a total of approximately 633) did the combined vote total of Dumanis and Fletcher exceed 50%.

Clairemont will be a high-stakes voter battleground for DeMaio and Filner in November. Many voters in Clairemont were divided in their choice for mayor and was the most competitively fought over community in the City. It is likely that both mayoral campaigns will be spending significant time in the area, and will recruit popular, well-known local leaders (Donna Frye, Councilmember Lorie Zapf) to solicit votes in the general election.

Candidates will have to prepare for a different election in the fall. The voting electorate for primary elections in San Diego is significantly smaller than general elections, particularly in presidential election years. Consider that in the last primary election in a presidential year (2008), voter turnout countywide was 33.99%, while the fall voter turnout was 83.72%. DeMaio and Filner will have to shore up their partisan voter base, while reaching out to younger, diverse, and Decline to State voters to achieve victory on Election Day.

The NUSIPR Election brief can be found here.