Jack Benny first appeared on radio as a guest of Ed Sullivan in 1932. He was then given his own show later that year, with Canada Dry Ginger Ale as a sponsor — The Canada Dry Program, beginning May 2, 1932, on the NBC Blue Network and continuing there for six months until October 26, moving the show to CBS on October 30. With Ted Weems leading the band, Benny stayed on CBS until January 26, 1933.
Arriving at NBC on March 17, Benny did The Chevrolet Program until April 1, 1934. He continued with The General Tire Revue for the rest of that season, and in the fall of 1934, for General Foods as The Jell-O Program Starring Jack Benny (1934–42) and, when sales of Jell-O were affected by sugar rationing during World War II, The Grape Nuts Flakes Program Starring Jack Benny (Later The Grape Nuts and Grape Nuts Flakes Program) (1942–44). On October 1, 1944, the show became The Lucky Strike Program Starring Jack Benny, when American Tobacco's Lucky Strike cigarettes took over as his radio sponsor, through the mid-1950s. By that time, the practice of using the sponsor's name as the title began to fade.
The show returned to CBS on January 2, 1949, as part of CBS president William S. Paley's notorious "raid" of NBC talent in 1948-49. There it stayed for the remainder of its radio run, which ended on May 22, 1955. CBS aired repeats of previous 1953-55 radio episodes from 1956 to 1958 as The Best of Benny for State Farm Insurance, who later sponsored his television program from 1960 through 1965
The format of The Jack Benny Program never wavered. The program utilized a loose show-within-a-show format, wherein the main characters were playing versions of themselves. There was not really a fourth wall, per se. The show would usually open with a song by the orchestra or banter between Benny and Don Wilson. There would then be banter between Benny and the regulars about the news of the day or about one of the running jokes on the program, such as Benny's age, Day's stupidity or Mary's letters from her mother. There would then be a song by the tenor followed by situation comedy involving an event of the week, a mini-play, or a satire of a current movie. Some shows were entire domestic sitcoms revolving around some aspect of Benny's life (spring cleaning, or a violin lesson).
Although Eddie Anderson's Rochester may be considered a stereotype by some, his attitudes were unusually sardonic for such a role, and Benny treats him as an equal, not as a servant. In many routines, Rochester gets the better of Benny, often pricking his boss' ego, or simply outwitting him. The show's portrayal of black characters could be seen as advanced for its time; in a 1956 episode, African-American actor Roy Glenn plays a friend of Rochester, and he is portrayed as a well-educated, articulate man, not as the typical "darkie stereotype" seen in many films of the time.
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