Democratic Party candidate John Garamendi won against Republican opponent David Harmer.

On May 5, 2009, President Barack Obama nominated Democratic Representative Ellen Tauscher for the position of Undersecretary of State for Arms Control and International Security.

[1] She was confirmed by the United States Senate on June 26 and subsequently resigned from her congressional seat.

As that didn't occur, the general election took place on November 3, 2009, between the candidates with the most votes for each party.

Denham, Cloward, and McIlroy were the only candidates from their parties so they advanced the general election by default.