Oregon was admitted to the Union on February 14, 1859. Its current U.S. senators are Democrats Ron Wyden (serving since 1996) and Jeff Merkley (serving since 2009). Mark Hatfield was the state's longest serving senator (1967–1997). Prior to 1906, U.S. senators were elected by the Oregon Legislative Assembly. In 1904, Oregon voters passed a ballot measure that required U.S. senators to be selected by a popular vote and then endorsed by the state legislature. Beginning in 1914, U.S. senators were directly elected by popular vote on the basis of the 17th Amendment to the United States Constitution.

List of senators

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