Thomas Edmund Dewey (March 24, 1902 – March 16, 1971) was the 47th Governor of New York (1943–1954). In 1944 he was the Republican candidate for President, but lost to President Franklin D. Roosevelt in the closest of Roosevelt's four presidential elections. In 1948, he was again the Republican candidate for president, but lost to the incumbent president, Harry S. Truman, in one of the greatest upsets in presidential election history.

Dewey led the progressive/moderate faction of the Republican Party, in which he fought conservative Ohio Senator Robert A. Taft. Dewey was an advocate for the professional and business community of the Northeastern United States, which would later be called the "Eastern Establishment." This group supported most of the New Deal social-welfare reforms enacted during the administration of Franklin D. Roosevelt, and it consisted of internationalists who were in favor of the United Nations and the Cold War fight against communism and the Soviet Union. In addition, he played a large part in the election of Dwight D. Eisenhower as President in 1952. Dewey's successor as leader of the progressive Republicans was Nelson Rockefeller, who became governor of New York in 1959. The New York State Thruway is named in Dewey's honor.