This win gives the Democrats a 57-seat Senate majority, including Independent Sen. Joe Lieberman.
Through the campaign Gordon, a moderate, attempted to associate himself with Democratic presidential candidate Barack Obama. Gordon did this most notably in one of his ads about the environment.
"Who says Gordon Smith helped lead the fight for better gas mileage and a cleaner environment," the ad asked. "Barack Obama."
Gordon was first elected to the Senate in 1996.