The Courier-Journal of Louisville reported that Rush's attorney, Robert Farmer of Toronto, had sent the letter to the Paul campaign. Farmer told the newspaper his objection is not political.
The Paul campaign had used one song by Rush, which was founded in the late 1960s, at a rally in Kentucky and another song as background in a fundraising video.
Paul campaign manager Jesse Benton said Wednesday that he had received the letter. He called it a non-issue.
Such flaps between politicians and professional musicians are not uncommon.
