Attorney for Manhattan, had risen to national fame as the "Gangbuster" prosecutor who had sent numerous infamous Mafia figures to prison, most notably Lucky Luciano, the organized-crime boss of New York City. Dewey had won most of the presidential primaries in the spring of 1940, and he came into the Republican Convention in June with the largest number of delegate votes, although he was still well below the number needed to win. Vandenberg, the senior Republican in the Senate, was the "favorite son" candidate of the Michigan delegation and was considered a possible compromise candidate if Taft or Dewey faltered. Former President Herbert Hoover was also spoken of as a compromise candidate. However, each of these candidates had weaknesses that could be exploited. Taft's outspoken isolationism and opposition to any American involvement in the European war convinced many Republican leaders that he could not win a general election, particularly as France fell to the Nazis in June 1940 and Germany threatened the United Kingdom. Dewey's relative youth—he was only 38 in 1940—and lack of any foreign-policy experience caused his candidacy to weaken as the Wehrmacht emerged as a fearsome threat. In 1940, Vandenberg was also an isolationist (he would change his foreign-policy stance during World War II) and his lackadaisical, lethargic campaign never caught the voters' attention. Hoover still bore the stigma of having presided over the Wall Street Crash of 1929 and the subsequent Great Depression. This left an opening for a dark horse candidate to emerge. A Wall Street-based industrialist named Wendell Willkie, who had never before run for public office, emerged as the unlikely nominee. Willkie, a native of Indiana and a former Democrat who had supported Franklin Roosevelt in the 1932 United States presidential election, was considered an improbable choice. Willkie had first come to public attention as an articulate critic of Roosevelt's attempt to break up electrical power monopolies. Willkie was the CEO of the Commonwealth & Southern Corporation, which provided electrical power to customers in eleven states. In 1933, President Roosevelt had created the Tennessee Valley Authority (TVA), which promised to provide flood control and cheap electricity to the impoverished people of the Tennessee Valley. However, the government-run TVA would compete with Willkie's Commonwealth & Southern, and this led Willkie to criticize and oppose the TVA's attempt to compete with private power companies. Willkie argued that the government had unfair advantages over private corporations,