19. Failing twice as the Republican presidential nominee, Thomas Dewey’s historic defeat in the 1948 campaign against Harry Truman is widely regarded as one of the biggest upsets in American political history
Riding the coat-tails of a successful career as a New York City District Attorney, including acting as the prosecutor against Charles “Lucky” Luciano, Thomas Dewey served as the 47th Governor of New York from 1943 to 1954. Becoming a leading member of the progressive wing of the Republican Party, advocating an internationalist stance supportive of the United Nations as well as defending many of the progressive social and welfare reforms of the New Deal, Dewey enjoyed the less than enviable task of contesting the 1944 presidential election against incumbent Franklin D. Roosevelt.
With the United States performing well in the Second World War, despite his long tenure Roosevelt was unassailable, winning an unprecedented fourth term in office by thirty-six states to Dewey’s twelve. Dewey’s ignominy, however, stems from the 1948 presidential election. Selected once again as the Republican nominee, Dewey was widely expected to emerge victorious due to Truman’s low approval ratings and a split within the Democratic Party. Nevertheless, an unenergetic and stale campaign by Dewey precipitated a stunning loss to Truman by 303 to 189 Electors. Providing the Democrats, who had won twenty-eight to sixteen states, a fifth consecutive presidential election victory, Dewey’s loss was lampooned further by newspaper headlines proclaiming in advance his widely expected victory.