After graduating, he taught school for several years before turning professional during the mid-1930s, serving as a sideman and arranger for Count Basie, Tommy Dorsey, Raymond Scott, Claude Thornhill and others.
[1] Winterhalter also arranged and conducted sessions for singers including Dinah Shore and Billy Eckstine, and in 1948 he was named musical director at MGM Records.
In 1950, Winterhalter moved to RCA Victor, where he arranged sessions for most of the label's pop recording artists of the era including Perry Como, Harry Belafonte, Eddie Fisher, Jaye P. Morgan, Eartha Kitt and the Ames Brothers.
Winterhalter also notched a series of chart hits, including "Mr. Touchdown, U.S.A.", "A Kiss to Build a Dream On", "Blue Tango", "Vanessa", "The Little Shoemaker", and "Song of The Barefoot Contessa".
His other motion picture credits include work as conductor and arranger for Eddie Fisher and Debbie Reynolds in the 1956 musical comedy, Bundle of Joy, and orchestrator for Thrill of a Romance (1945) and Meet the People (1944).