Carl Trumbull Hayden was an American politician and the first United States Senator to serve seven terms. Serving as Arizona's first Representative for eight terms before entering the Senate, Hayden set the record for longest-serving member of the United States Congress more than a decade before his retirement from politics. The longtime Dean of the United States Senate 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.
Having earned a reputation as a reclamation expert early in his congressional career, Hayden consistently backed legislation dealing with public lands, mining, reclamation, and other projects affecting the Western United States. In addition, he played a key role in creating the funding formula for the federal highway system. President John F. Kennedy said of Hayden, "Every Federal program which has contributed to the development of the West—irrigation, power, reclamation—bears his mark, and the great Federal highway program which binds this country together, which permits this State to be competitive east and west, north and south, this in large measure is his creation."Known as the "Silent Senator", Hayden rarely spoke on the Senate floor. Instead his influence came from committee meetings and Senate cloakroom discussions where his comments were "given a respect comparable to canon law". A colleague said of him, "No man in Senate history has wielded more influence with less oratory," while The Los Angeles Times wrote that Hayden had "assisted so many projects for so many senators that when old Carl wants something for his beloved Arizona, his fellow senators fall all over themselves giving him a hand. They'd probably vote landlocked Arizona a navy if he asked for it."