After a tour of duty in World War II, and more work with dance bands in the Buffalo New York area, he was hired in October 1952 by NBC director E. Roger Muir, at the request of Bob Smith (who Nicholson had worked with in Buffalo), for The Howdy Doody Show, formerly known as "Puppet Playhouse".
At Nicholson's request, he was replaced as Clarabell by musician Lew Anderson in 1954 and reverted to his role of Corny Cobb, which he kept until the end of the show in 1960.
[3] Prior to joining The Howdy Doody Show, Nicholson formed the studio Soundac, which is best known for producing the animated series Colonel Bleep.
[5] Nicholson got his nickname of "Nick" on the show, as there were up to six men named "Bob" on the cast and crew at any given time.
[7] Nicholson also assumed the role of Corny Cobb for the revival of Howdy Doody in 1976–1977 and at a 40-year anniversary special in 1987.