Below is a chronological listing of the United States senators from Delaware. U.S. senators were originally elected by the Delaware General Assembly for designated six-year terms beginning March 4. Frequently portions of the term would remain only upon a U.S. senator's death or resignation. From 1914 and the enforcement of the Seventeenth Amendment to the United States Constitution, adopted in 1913 but rejected by the General Assembly that year and not ratified until July 1, 2010, officeholders were popularly elected on the first Tuesday after November 1; starting 1935, the beginning of their term is January 3. Delaware's current U.S. senators are Democrats Tom Carper (serving since January 3, 2001) and Chris Coons (serving since November 15, 2010). Joe Biden is Delaware's longest serving senator (1973–2009).

List of senators

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