Former Republican Rep. Bob Barr announced on Monday that he is running for President. This time around, Barr hopes to snag the Libertarian nomination.

Barr has hired Ross Perot's former campaign manager to head his bid.

"I've heard from Americans from all walks of life ... they want a choice," he said at a news conference in Washington. "They believe that America has more and better to offer than what the current political situation is serving up to us."

This could shake everything up. Bob Barr could hurt McCain since they're both basically moderate Republicans, and it could hurt the Democratic nominee since Barr would represent a call for change.

The Libertarians will pick their nominee on Memorial Day Weekend.