(CNN) -- Wednesday night's CNN debate lands at a critical moment in the Republican race.
This season, each debate has set the tone for the primary to follow. Newt Gingrich's savaging of the media helped propel him to victory in South Carolina. Mitt Romney's savaging of Gingrich helped him to clinch Florida. The current uncertainty about the race, and the extraordinary elasticity in the polls, is partly due to the fact that we haven't had a debate for a whole month.
It's important, then, for each of the candidates to make a powerful impression in this last confrontation before Arizona and Michigan vote on February 28. Rick Santorum and Newt Gingrich will compete over who is the most conservative, and Ron Paul will push his unique brand of libertarianism. Same old, same old. But we might see something new from Mitt Romney: a glimmer of humanity.
The latest CNN/Time/ORC International Poll shows that Santorum is closing the gap on Romney in Arizona, but it's probably in Michigan that he stands the best chance of scoring an upset. A week ago, polls put Santorum as much as 10 points ahead in the Great Lakes State. But now they call it a statistical dead heat between him and Romney.
So it would serve Santorum well to hit Mitt hard in the debate. This is Rick's natural style -- he gets a thrill out of counting the flaws of his opponents. But Santorum also probably recognizes that the only way he'll win Michigan is by reminding voters of the doubts that they have about Romney's conservatism. That's what he's been doing in the western part of the state all this week, where he has hit out repeatedly at Romney's "well-oiled weathervane" stance on issues like abortion and Iran.
One thing Santorum doesn't particularly need to do in the debate is make voters like him: They already do. According to Public Policy Polling, he has a favorability rating among Michiganders of 67%.
Santorum's enduring popularity is partly thanks to the fact that Romney hasn't been spending his money on an excessive number of attack ads, as he did in Florida. Instead, Romney has been working hard on his own favorability rating in Michigan, which has crept up from 49% to 55%.
Hitherto, Mitt has suffered from the "weirdo factor" -- the sense that he's not quite like you and me. The press has given a lot of coverage to the Mormon practice of giving "proxy baptisms" to deceased nonbelievers, something that Romney admits he has done, but not "recently." This has been compounded by the strange tale of Romney's dog, Seamus, who Mitt once drove to Canada strapped to the roof of his car. Poor Seamus apparently lost bowel control en route and ran away on arrival. Googlers have tried to turn "Romney" into a verb that means "to soil oneself with fear." Here's an example of it used in a sentence: "Every time I think of Newt Gingrich being elected president, I Romney uncontrollably."
But Mitt has been countering the "weirdo factor" with a series of ads and personal appearances in Michigan that emphasize his local roots and his concern for the auto industry in a state beset by tragic levels of unemployment. This is the strategy that we can expect him to take in Wednesday's debate: folksy and populist. There will be a lot about how great American cars are, Mitt's experience as a businessman, Obama's relative incompetence and Romney's Michigan childhood.
Whether it will work is a matter of judgment. On the campaign trail, Romney's idea of soaring rhetoric usually involves singing highlights from "America the Beautiful." Efforts to appear humble are frequently undermined by an ironic statement (remember the $10,000 bet?), and intimate stories about his father are so formulaic they sound as if he learned them by rote. The only way Romney could break the spell of his own emptiness would be to crash sobbing into the arms of Ellen DeGeneres.
But if Romney's reinvention as a human being does pay off, it will be because Republicans desperately want it to work. Republicans still tell pollsters that they think Mitt is the most electable candidate. If they could only be convinced that he is as conservative as they -- or at least as human -- they would probably fall in behind him. A bit of passion and compassion in Wednesday's debate could be all the excuse wavering Republicans need to back a winner.
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The opinions expressed in this commentary are solely those of Timothy Stanley