City Councilman Richard Caliguiri, a rising star in city politics (and future mayor) filed to run against Flaherty in the primary. Because Flaherty had long antagonized the remnants of the city's archaic Democratic machine, the aging party bosses endorsed Caliguiri, even though both Democratic candidates had similar legacies as a reformer. However, the popular mayor earned a moderate victory despite tepid support from insiders.
No Republicans filed to run in the primary; however, Flaherty won, by write-in, the Republican primary. The popular mayor received nearly 80% of his vote total on the Democratic line, which is in line with party registration in the city. A total of 67,550 votes were cast.
- "Republican mayoral candidates through the years". Pittsburgh Post-Gazette. 7 November 2007. Retrieved 18 September 2009.
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