He was appointed
Assistant Secretary of State for Public Affairs and held the position from August 31, 1945 to September 30, 1947, during which time he was active in organizing the
United Nations. He was appointed to the
United States Senate on 17 December 1949 by his old partner Chester Bowles (who had been elected Governor in 1948), and subsequently elected in the
special election on 7 November 1950 as a
Democrat to fill the vacancy caused by the resignation of
Raymond E. Baldwin in December 1949 for the remainder of the term ending 3 January 1953. In the November 1950 election, he defeated
Republican party candidate
Prescott Sheldon Bush, father of U.S. President
George Herbert Walker Bush and grandfather of U.S. President
George W. Bush by 1,102 votes. In 1951 he introduced a resolution to expel
Joseph McCarthy from the Senate. Benton provided 30,000 words of testimony on Sept. 28, 1951 in support of Senate Resolution 187. Due to Benton's resolution and McCarthy's response, the Senate Rules committee investigated and criticized both of them but punished neither. On television, when asked if he would take any action against Benton's reelection bid, McCarthy replied, "I think it will be unnecessary. Little Willie Benton, Connecticut's mental midget keeps on... it will be unnecessary for me or anyone else to do any campaigning against him. He's doing his campaigning against himself." Benton lost in the
general election for the full term in 1952 to
William A. Purtell. Benton's comeback bid failed in 1958 when, running against Bowles and
Thomas Dodd he failed to win the Democratic nomination for the U.S. Senate. He was later appointed
United States Ambassador to
UNESCO in
Paris and served from 1963 to 1968. Benton served on the board of trustees of the
University of Connecticut from 1957 to 1972. Converted to a museum in 1966, the
William Benton Museum of Art on the university's main campus in
Storrs was named in his honor in 1972. Benton had donated his personal collection of works by
Reginald Marsh to the museum. ==Encyclopædia Britannica and further civic life==