If there was any surprise in the first 90-minute presidential debate, it was President Obama's apathetic performance, not Mitt Romney's energetic and assertive pounding of the commander in chief.

Anyone who had caught Romney's performances in the 23 debates he participated in before and during the Republican primaries, or his debates in Massachusetts when he ran for office there, would have expected Romney to be a smiling, numbers spewing, lively and aggressive political combatant bent on persuasion.

Romney's style, reminiscent of the corporate deal-maker — which isn't surprising since that's what he once was — has come under attack from his political opponents.

After the Oct. 3 debate, Obama sought to deflate Romney's obvious win by telling an audience at a San Francisco fundraiser: "But I want everybody to understand something: What was being presented wasn't leadership; that's salesmanship."

Former President Bill Clinton had a more colorful description of Romney, as having the soul of a Bain Capital deal-maker who will do whatever it takes to close the transaction.

Of course, an obvious response to all of this is that part of presidential leadership is salesmanship, something Clinton probably knows better than most, and an area where Obama has been lacking — and not only at the first presidential debate.

As someone from the world of business meetings who has undoubtedly done a prodigious number of PowerPoint presentations, Romney is obviously comfortable with data and facts.

You could almost see the bullet points when Romney started off the first debate by concisely ticking off his economic plan:

"My plan has five basic parts. One, get us energy independent, North American energy independent. That creates about 4 million jobs. No. 2, open up more trade, particularly in Latin America; crack down on China if and when they cheat. No. 3, make sure our people have the skills they need to succeed and the best schools in the world. We're far away from that now. No. 4, get us to a balanced budget. No. 5, champion small business."

And that wasn't the only time he used audible bullet points. He was a veritable human PowerPoint at the first debate.

"What made him so effective in some of the debates during the primaries and the first [presidential] debate is that he seemed to have control of the facts and the numbers," said James Roland, a debate coach at Emory University. "Now, obviously it's up for debate if those numbers are correct. But he comes across as being knowledgeable. And I think that lends itself to credibility to the audience."

Because he had a handle on so much data ( though not all of it accurate; and neither was all of Obama's), Romney was able to throw a series of charges at the president, knowing there would never be enough time for Obama to respond to them all. Maybe he also figured it would force Obama to spend time taking notes, which resulted in images of Obama with his head down for much of the evening.

Here's an example of one particularly jam-packed Romney paragraph. He made it in response to Obama's charge that Romney wants to cut the federal education budget, a charge Romney rejected:

"But you make a very good point, which is that the — the place you put your money makes a pretty clear indication of where your heart is. You put $90 billion into — into green jobs. And — and I — look, I'm all in favor of green energy. Ninety billion (dollars) — that — that would have — that would have hired 2 million teachers. Ninety billion dollars. And these businesses — many of them have gone out of business. I think about half of them, of the ones have been invested in, they've gone out of business. A number of them happened to be owned by — by people who were contributors to your campaigns."

Even if Obama challenged that array of data, which he didn't, it would have taken a lot longer to rebut those accusations than it took Romney to make them.

That technique worked so well, it would be amazing if Romney didn't repeat something similar at Tuesday's debate.

Romney also is very mission oriented when he enters a debate or makes a speech. Because he's analytical by nature, according to people who know and have studied him, he usually knows what he wants to accomplish in a debate.

In the first debate, it was fairly clear he wanted voters to view him as a man of action and as a leader who could not only match the president's command presence, but exceed it.

And because so much of his argument for why he should be president is based on his business success, projecting the image of the successful CEO was vital. And never did he seem more the successful CEO than when he said to Obama: "The second topic, which is you said you get a deduction for getting a plant overseas. Look, I've been in business for 25 years. I have no idea what you're talking about. I maybe need to get a new accountant."

Because he takes the offensive in debates to show his rivals and voters who's top dog, Romney can sometimes misstep. There was his well-known blunder during a GOP debate in which he bet Texas Gov. Rick Perry $10,000 to settle a disagreement about whether or not a certain statement appeared in Romney's book.

It wasn't the only time Romney has overplayed his hand in a debate. In The Real Romney, a biography by journalists Michael Kranish and Scott Helman, they report that in a debate during the 1994 Senate race against Sen. Edward Kennedy, Romney sought to portray himself as a more energetic advocate of women in the workplace than Kennedy. Romney asked Kennedy, who was only the Senate's leading liberal, what he'd do to break the glass ceiling impeding women's progress.

The authors write:

"Almost smiling as he cited his legislative record, Kennedy said, 'You're not going to find a member of the U.S. Senate that's a stronger supporter.' Robert Shrum, Kennedy's senior adviser, said at the time 'That question was like asking Babe Ruth how to hit a ball.'"

Romney's first debate with the president lacked any significant gaffes like those. But Tuesday's debate is in the town hall format, in which the audience of undecided voters chosen by Gallup will ask questions. That setting could prove more challenging to Romney than the first debate, with the possibility an audience member could ask a question that Romney hasn't prepared for.

But Romney has done numerous town hall-style events where he's taken questions from audience members, though they have admittedly generally been groups of his supporters.

Indeed, his campaign had him do such a town hall in Ohio last week in preparation for Tuesday's debate.

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