This is the first study to fully explore Marcantonio's unique status as a radical politician who, despite massive opposition, held high public office for fourteen years. As congressional representative to Harlem, he became the leader of the most important third party in the United States, the American Labor Party, and achieved national stature as a spokesman for the left. The book demonstrates Marcantonio's transcendence of a number of American truisms. Meyer explores the efficiency of Marcantonio's political machine, the unusual alliance of his two major political bases (East Harlem and El Barrio), and his open relationship with the Communist Party.