By the mid-1950s, rock and roll had become wildly popular across the color line. A number of factors contributed: This was in part because white teens secretly tuned in to black radio stations to hear the new sound. Scrambling to fill airtime due to increasing competition from television, white radio networks were more willing to turn to music which was outside of the mainstream, including up-andcoming rock and roll artists. Rock and roll was also made popular with white listeners thanks to the widespread phenomenon of white singers making covers of previously recorded black songs.