Tonight, Mitt Romney has the opportunity to change the trajectory of this race against Barack Obama in the first of three presidential debates.  This is arguably the most important of the three, as low-information voters may be getting their first close look at Mitt Romney since the primary debates ended months ago — or perhaps ever.  In my column for The Week, I game out the stakes in this Denver debate, and offer three keys to Romney’s strategy:

1. Romney has to transcend the debate agenda. Successful candidates use questions as mere suggestions, while answering their own questions to drive a debate narrative. Both Obama and Romney will do this, but Republicans assume that media moderators will drive the debate into territory friendlier for Obama than Romney. Romney has to take control and drive the debate, not let the moderator keep him pinned on defense — and that’s an entirely legitimate strategy for voters, too. As Romney is running against an incumbent president, the focus should be on Obama’s performance and his plans for a second-term agenda.

2. Romney has to assert himself without looking overly aggressive. That’s no easy feat. Al Gore lost the debate battle against George W. Bush by alternately looking too aggressive and then too impatient. Obama ended up prevailing over John McCain by projecting a collegial-if-not-friendly mien while dispensing with McCain’s arguments. Lower-information voters have to see Romney as something other than the Thurston Howell caricature that Team Obama has painted, while still pressing Obama on his economic failures and lack of any clear second-term agenda.  The tone used in his ad last week, in which he spoke directly into the camera for 60 seconds about the economy, would work well in this setting to reassure undecided voters that Romney will be a safe alternative to Obama.

3. Romney has to construct an overarching narrative of executive incompetence in the Obama White House. This first debate will focus on the economy, but Romney needs to draw on more issues than that to make his case. Obama will respond on the economic issues by claiming that the grave nature of the recession handicapped the recovery, and that his policies will eventually work to create jobs faster than population growth, a pace with which the Obama recovery has failed to keep up. Romney needs to use the economy to discuss the inept handling of consular security in Benghazi and the Arab Spring in general, as well as Operation Fast and Furious, to show that the entire administration has run off the rails. That will negate Obama’s blame-Bush-and-Republicans defense for the economy, and strengthen Romney’s case that Obama simply doesn’t have the executive talent for his current position.

Actually, it will be interesting to see whether Romney has to force the issue of Benghazi into the debate.  The announced topic is domestic policy, but BuzzFeed’s Michael Hastings reported yesterday that the moderator, PBS’ Jim Lehrer, has all the leeway he needs to go beyond the announced agenda:

According to the Commission on Presidential Debates, tomorrow’s moderator, PBS anchor Jim Lehrer, has the leeway to ask any questions he wants — including topics dominating the headlines, as Libya is now.

“We don’t have any say in what the moderator asks whatsoever,” the spokesperson for the Presidential Debate Commission Bob Roy told BuzzFeed. “The only rule for the debates is that the moderator decides what is asked.”

A spokeswoman for Lehrer, Anne Bell, told BuzzFeed in an email that “the overall debate topic is domestic policy” but that “when Jim Lehrer announced the general topics for the debate he did indicate that is was subject to change in the event news warranted.”

I’d expect that to come early in the debate, either through Lehrer or through Romney.  Will Barack Obama be prepared for that?  Supposedly he’s shirking his debate prep in Nevada, and that’s not uncommon, according to the man who prepped Jimmy Carter for his disastrous debate performance against Ronald Reagan in 1980.  Samuel Popkin has written a book about incumbents and debates, and argues that incumbents get too wrapped up in sycophantic bubbles to prepare properly for debates — and have little stomach for practice, too:

Samuel Popkin, a political-science professor at the University of California (San Diego), advised three Democratic nominees before their debates. He was brought to Camp David in 1980 to play the role of Reagan in debate prep for Carter. Like Stockman four years later, Popkin incurred the wrath of his president, as he disclosed for the first time in his new book, The Candidate: What It Takes to Win—and Hold—the White House. Aides knew that Carter was unprepared for Reagan and ordered Popkin to “hold nothing back.” So in his very first answer, he used Reagan’s own words to pummel the president. “I could see that Carter was bewildered. When I spoke he would alternately feign a smile or wrinkle his nose in disgust; look away from me in embarrassment or glare at me in anger,” he wrote.

Popkin told National Journal, “I really thought the Secret Service was going to kneecap me. Carter turned red in the face and got flustered, and, after only 11 minutes he said, ‘That is enough’ and tried to call it off.”

Popkin said he had always believed that reaction was unique to Carter until he started researching his book and discovered that every incumbent resists the prep work and reacts badly to being challenged. “Nobody on staff ever questions a president’s motives and nobody around him ever challenges him,” he said, contending there is very much an “emperor-has-no-clothes” aspect for leaders who have spent four years sheltered in the protective presidential bubble and surrounded by sycophantic aides.

Then add to that resistance the fact that incumbents are almost always rusty when it comes to debating. Romney this year has spent 43 hours in 23 separate debates. Never flashy, he was solid and disciplined, clearly losing only one debate when he impulsively challenged Texas Gov. Rick Perry to make a $10,000 bet. In contrast, Obama has not debated in four years. And while he improved as a debater over the course of 2008, he stumbled far more often than Romney did this year. Obama was too often professorial and discursive and found it difficult to be concise. He promised in one debate to meet with America’s enemies with no preconditions, and in another he was seen as cruel to Hillary Rodham Clinton when he coldly assessed her likability. In his general-election debates, he was blessed with low expectations against the much more experienced John McCain.

National Journal also games out the potential domestic-policy topics that will arise, and provides a good (if necessarily brief) analysis of how each topic may play for Romney and Obama.  Andrew Malcolm analyzes the stakes, and the way candidates react to the “high wire” act:

But these debates are rarely important as individual events. Instead, taken together they provide an impressionistic narrative arc for viewers to soak up what these men are about, how they carry themselves, listen, speak under pressure.

From a living room couch, voters may ponder the unimaginable pressures at play. It’s true. They’re intense. It’s bad for staffers, worse for spouses.

But at this level of politics, the candidates I’ve seen up close actually relish the moment. They enjoy walking the high-wire. They’ve campaigned typically for years, sometimes with an audience of but one or two. Now, their every word will reach scores of millions.

And whoever said seeking the pressurized presidency should be easy? ….

The Republican needs to be aggressive without stridency, to look like he’s willing to fight for the job, which he did at times during the 220 Republican primary debates. (OK, it just seemed that way; there were ‘only’ 22).

Romney needs to confront Obama over the weeks of false ads that have given the Democrat poll leads in crucial swing states. With no economic record to run on and no second-term agenda beyond the slogan “Forward,” Obama is likely to play considerable defense. He wants to avoid any mistakes that would elevate Romney’s stature by comparison.

History shows that the debates usually result in elevated status for the challenger no matter what, thanks to the difficulty of playing defense in debates.  That’s probably going to be the case tonight as well, if Romney remains as focused and disciplined as he was in the primary debates.

Note: We’ll be covering tonight’s debate, of course, but I won’t be available to watch it live, thanks to a commitment at school this evening.  Be sure to follow Mary Katharine Ham and Erika Johnsen on Twitter for their analysis.