DCCC is a commonly-used acronym for the San Francisco Democratic County Central Committee, a chief organizing body for the Democratic Party in SF. 

Description from web site (accessed June 3, 2015). 
"San Francisco's Democratic County Central Committee, or DCCC, is the governing body of the local Democratic Party as defined in California's Government Code and Elections Code. The DCCC is comprised of local Democrats elected by voters in each Assembly District, as well as partisan-level Democratic elected officials and nominees who serve as Ex-Officio Officers."

Website:  http://www.sfdemocrats.org/