In the general election, there were 39 races with both Democratic and Republican candidates; 24 were in districts previously represented by a Republican, 15 in districts previously represented by Democrats.

Eighteen incumbent House members and six incumbent Senators earned enough write-in votes in the opposing party's primary to earn a dual endorsement.

[1] Every two years, half of the state senate seats come up for election.

In 2008 there was also an election for District 17, resulting from Senator Brad Avakian's appointment to Oregon Labor Commissioner.

The other seven seats were previously held by Republicans, and four of them were contested by both major parties.