Ke$ha, second from left, performs with backup dancers during the second night of KIIS FM's Jingle Ball at Nokia Theatre LA Live on Monday, Dec. 3, 2012, in Los Angeles. (Photo by Chris Pizzello/Invision/AP)

Photo by: Chris Pizzello

Ke$ha, second from left, performs with backup dancers during the second night of KIIS FM's Jingle Ball at Nokia Theatre LA Live on Monday, Dec. 3, 2012, in Los Angeles. (Photo by Chris Pizzello/Invision/AP)