As part of the promotion for the first film, Singleton and Lake appeared as Blondie and Dagwood on the December 20, 1938 episode of The Pepsodent Show radio program, which starred Bob Hope.

In 1944, Blondie was on the NBC Blue Network, sponsored by Colgate-Palmolive's Super Suds, airing Fridays at 7 p.m. from July 21 to September 1.

The final three weeks of that run overlapped with Blondie's return to CBS on Sundays at 8pm from August 13, 1944, to September 26, 1948, still sponsored by Super Suds.

Beginning in mid-1945, the 30-minute program was heard Mondays at 7:30 p.m. Super Suds continued as the sponsor when the show moved to NBC on Wednesdays at 8 p.m. from October 6, 1948, to June 29, 1949.

Early in 1949, Colgate executive Bob Healy notified Singleton that the company desired "a different interpretation of the character", and an agency began auditioning actresses to be the new Blondie.