the campaign, these two men are by definition built to withstand pressure. Each known as a formidable debater. But tonight, it will be pressure like no other. They have to bring their a-games. And... See More
the campaign, these two men are by definition built to withstand pressure. Each known as a formidable debater. But tonight, it will be pressure like no other. They have to bring their a-games. And abc's jake tapper now tells us about each candidate's biggest move. Jake? Reporter: Good evening, diane. That's right. These are two very experienced debaters, with more than 50 presidential primary and general election debates between them. Though they have their weaknesses, they both have considerable strengths. As president obama touched down in denver, he brought the experience of 22 previous president debates, primary and general election with him. We've seen him draw upon his command in being able to make a bold pledge. If we have osama bin laden in our sights, and the pakistani government is unable or unwilling to take them out, then I think that we have to act and we will take them out. Reporter: And we've seen him tap his reservoir of righteousness to make a strong attack. You said we knew where the weapons of mass destruction were. You were wrong. You said that we were going to be greeted as liberators. You were wrong. Reporter: Tonight will be mitt romney's 36th presidential debate. Though his first as nominee. His team is hoping he'll show the agility we've seen him display. If people are looking for someone who will discriminate against gays, they won't find that in me. When is the last time you stood up and spoke out for increasing gay rights? Right now. Reporter: As well as his ability to jujitsu, to forcefully use an attack against his attacker. Mr. Speaker, I'm not an anti-immigrant. My father was born in mexico. My wife's father was born in wales. They came to this country, the idea that I'm anti-immigrant is repulsive. Reporter: And diane, take a look at this picture that the obama campaign sent out. It is from four years ago, in oxford, mississippi, then senator obama preparing for his first presidential debate AGAINST john McCain. Both candidates right now, mitt romney and barack obama, no doubt, very nervous. I'm nervous, just looking at that picture.
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