Republican presidential candidate Herman Cain has some musical competition. (Matt Sullivan/Getty Images)

Rick Santorum sings a snippet of Sinatra:

Mitt Romney sings a line of “Who Let the Dogs Out?”:

Jon Huntsman plays the piano to “Hit the Road Jack”:

Rick Perry dances and sings with rabbis for Hanukkah:

Herman Cain sings “The Impossible Dream”:

and “I Must Tell Jesus”:

and “Hold On”: