Kulongoski faced several challengers in his primary, whom he dispatched to win his party's nomination a second time, while Republican nominee Ron Saxton, the former Chair of the Portland Public Schools Board and a candidate for governor in 2002 emerged from a crowded primary.

In a hard-fought campaign, Kulongoski won re-election by a surprisingly wide margin, winning his second term as governor.

As of 2023, this marks the last occasion in which the following counties have voted Democratic in a gubernatorial election: Clackamas, Columbia, Marion, and Wasco.

[2] Though Westlund gathered the requisite signatures to be able to run, he eventually dropped out of the race in August, noting, "At the beginning of this campaign, I made a commitment to the people of Oregon, that I was in it to win it, and that I absolutely would not play a spoiler role.

"[3] Constitution Party nominee Mary Starrett was widely perceived to win votes largely at the expense of Saxton's campaign.