Ohio was admitted to the Union on March 1, 1803, and elects U.S. senators to class 1 and class 3. Its current U.S. senators are Democrat Sherrod Brown (serving since 2007) and Republican JD Vance (serving since 2023), making it one of seven states to have a split United States Senate delegation along with Arizona, Maine, Montana, Vermont, West Virginia, and Wisconsin. Not counting Vermont and Arizona, where independents have caucused with the Democrats since 2001 and 2023, Ohio has had the longest current split delegation, having had two senators from the opposite parties since 2007. John Sherman was Ohio's longest-serving senator (1861–1877; 1881–1897).

List of senators

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