Haley headlined in vaudeville as a song-and-dance comedian. One of his closest friends was Fred Allen, who would frequently mention "Mr. Jacob Haley of Newton Highlands, Massachusetts" on the air. In the early 1930s, Haley starred in comedy shorts for Vitaphone in Brooklyn, New York. His wide-eyed, good-natured expression gained him supporting roles in musical feature films, including "Poor Little Rich Girl" with Shirley Temple, "Higher and Higher" with Frank Sinatra and the Irving Berlin musical "Alexander's Ragtime Band". Both "Poor Little Rich Girl" and "Alexander's Ragtime Band" were released by Twentieth Century-Fox. Haley was under contract to them and appeared in the Fox films "Rebecca of Sunnybrook Farm" and "Pigskin Parade", marking his first appearance with Judy Garland.