Carl Trumbull Hayden (October 2, 1877 – January 25, 1972) was an American politician. Representing Arizona in the United States Senate from 1927 to 1969, he was the first U.S. Senator to serve seven terms. Serving as the state's first Representative for eight terms before entering the Senate, Hayden set the record as the longest-serving member of the United States Congress more than a decade before his retirement from politics. He was Dean of the United States Senate and served as its president pro tempore and chairman of both its Rules and Administration and Appropriations committees. He was a member of the Democratic Party.