Some of the biggest names in rap have been enlisted by Barack Obama to encourage young people to vote.
Beyonce Knowles, Jay-Z, P. Diddy, and Mary J. Blige attended the promote the vote rally in Philadelphia yesterday.
Sean 'diddy' Combs wore a t-shirt saying 'vote or die' and Beyonce urged youngsters to vote by donning a hat that said 'CHANGE'.
The four stars were busy over the weekend in Florida getting ready for the elections today.
See the celebs get serious below



























