The 2004 United States Senate election in Oregon was held on November 2, 2004. Incumbent Democratic U.S. Senator Ron Wyden won re-election to a second full term. As of , this is the most recent U.S. Senate race in Oregon in which any Eastern Oregon counties voted for the Democratic nominee, and it is Oregon's most recent U.S. Senate race where the winning candidate won a majority of the state's counties.
Wyden was unopposed in the Democratic primary.
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