Madonna has given U.S. leader Barack Obama her support as the President prepares to fight for re-election.

Performing in Washington, D.C. on Monday (24Sep12), the pop superstar heaped praise on Obama - linking him to Abraham Lincoln and Martin Luther King, Jr. as part of a video montage celebrating America's leading civil rights leaders.

And she told fans, "Y'all better vote for f**king Obama, Ok? For better or for worse, all right? We have a black Muslim in the White House.

"That's some amazing s**t. It means there is hope in this country. And Obama is fighting for gay rights, so support the man, godd**nit."