Ross Perot backs Romney

The man who ran one of the most successful third-party presidential bids in history is getting behind Mitt Romney's campaign.

Ross Perot announced his endorsement for the 2012 Republican nominee Tuesday, ahead of the second debate between Romney and President Obama.

"The fact of the matter is that the United States is on unsustainable course. At stake is nothing less than our position in the world, our standard of living at home, and our constitutional freedoms," Perot said in a statement. "That is why I am endorsing Mitt Romney in his quest for the presidency. We can't afford four more years in which national debt mushrooms out of control, our government grows, and our military is weakened. Mitt has the background, experience, intelligence, and integrity to turn things around. He has my absolute support."

Perot, a billionaire who remains one of the richest people in the country, ran for president in 1992 and 1996. 

His 1992 run earned historic support for a third-party candidate. In the race against Bill Clinton and then-president George H.W. Bush, Perot received nearly 19 percent of the popular vote.