Editor's note: Timothy Stanley is a historian at Oxford University and blogs for Britain's The Daily Telegraph. He is the author of "The Crusader: The Life and Times of Pat Buchanan."
(CNN) -- Vice Presidential debates are usually treated as bores or curios. The best you can hope for is a misstep that makes the headlines the next day -- think Dan Quayle comparing himself to Jack Kennedy or Bob Dole lambasting all those "Democrat wars." But the debaters are auditioning to be understudy, so they usually play it safe.
Record numbers tuned in to watch Biden vs. Palin in 2008 simply to see if Sarah Palin would go 90 minutes without humiliating herself or her running mate. Apart from some aggressive winking, she performed adequately and disaster was avoided. So two personalities who ought to have made for great TV were actually a little dull.
Thursday night's debate will be different, because it matters in a way that previous matchups have not.
Mitt Romney's performance in last week's debate seems to have shaken up the polls. That's not just because he did well, but also because the voters appear to be more undecided about the election than we thought they were (just look at the massive attitude shift that Pew reports among female voters). In such an environment, gaffes and good rhetoric count for a great deal. Recall that the debates proved just as important to deciding the Republican primaries, and one of the reasons why Romney won the primaries is that he was so good at the debates.
It also helps that these two men embody the differences between the two parties. Both are Catholics, but from contrasting traditions. Biden comes from the Vatican II generation for whom Catholic piety is centered on social justice and economic fairness. For him, government welfare programs are an extension of Christian charity -- and he's happy to embrace the cultural changes that have altered attitudes about contraception, women and gay rights.
By contrast, Ryan is part of the John Paul II generation of conservative Catholics who have often despaired of the American church's flirtation with liberalism. Ryan has a moral theology that sees government as sapping self-reliance, and abortion as the murder of the unborn. Between the two of them, we have the bifurcation of the Roman Catholic Church personalized: social conscience vs. natural law. That said, it's interesting to note that Ryan has been prepping for this debate with Ted Olson -- the man who provided legal assistance to pro-same-sex marriage campaigners. It's surprising that no movement conservatives have made a fuss about the company that Ryan keeps.
In this contest between Catholics, who stands the better chance of winning? Paul Ryan, and for three reasons.
First, Ryan is younger. In last week's debate, despite being the older man, Romney came across as more youthful and energetic than the president. He looked not only ready to lead, but also more willing. Likewise, Ryan is a handsome, athletic young man who hunts deer with a bow and arrow. Already the star of an internet "Hey Girl" meme, he will reinforce the impression that the GOP ticket is the more virile.
Second, Biden is a more erratic performer than Ryan and so more likely to make a blunder. A good drinking game to play during the debate would be to take a shot every time Biden says "literally," another if he mispronounces someone's name, and another if he forgets Paul Ryan's. His tendency toward hyperbole and emotionally charged gaffes is notorious. The flip side of that problem is that if he keeps his natural energy too much in check, then he won't seem like the same old Biden that Democrats know and love. In 2008, he was outperformed by Sarah Palin partly because he seemed to be playing the statesman. As a rule, Biden does better in front of loud, sympathetic audiences (see his barnstorming convention speech).
Third, the issue momentum is with Romney/Ryan. It's true that Friday's jobs report lowered the unemployment rate and brought some good news to the administration. But it doesn't seem to be reflected in the polls yet. That might be because many Americans don't feel like things are getting better -- because so many are quitting the labor market or getting part-time work. Add to that some of the negative reports about the administration's handling of the Middle East and you get the sense that this week belongs to the Republicans.
Whoever wins, what is reassuring for fans of politics is the importance that debate has played in this election. With millions of dollars spent on negative ads and the Internet awash with silly stories about dogs on cars and old speeches, it's nice to know that uninterrupted, rational debate spread over just 90 minutes can still make such an impact in contemporary American democracy. Biden vs. Ryan is far from Lincoln vs. Douglas, but the spirit lives on.
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The opinions expressed in this commentary are solely those of Timothy Stanley.