The most practical – or, at least, the more practical – Republican candidate is, after all the high jinks, supposed to win, which has been the singular case for Mitt Romney. But it is now suddenly quite possible that the least-practical, most far-fetched figure, will pull it off.

This is a level of implausibility not just in the context of this campaign, but in history. There has never been a major party candidate as far from the norm as Rick Santorum – unless, that is, he's about to redefine the norm. Not even Barry Goldwater, the rightwing hawk whose 1964 loss remains the Republican party's biggest ever, was this far from the mainstream.

If Santorum wins next week in Michigan and Arizona, now distinct possibilities, that would come close to assuring this fabulous outcome. It's a kind of development that the earnest and process-oriented political media – believing that politics, by its nature, reflects the norm – seem so far unable to characterize effectively. Even the hysterical and shambolic nature of the Republican field over two cycles has not seemed to prepare anyone for how to account for Rick Santorum's possible nomination. Everybody is still quite deadpan. Nobody's yet officially gobsmacked.

There's almost a kind of private joke aspect to what's happening here: the liberal press seems to have cagily and humorously exercised its bias by not piling on Rick Santorum, hence helping him and hurting the Republicans. Or the joke all along has been Romney: a candidate so perversely unlovable that every clown has been able, however briefly, to be his contrast gainer.

This is what we know: the anti-Romney ideal is much stronger than Romney himself. The combined anti-Romney numbers have won handily in every primary so far (even in New Hampshire, Romney's only big win, Gingrich, Paul, and Santorum beat him). And because politics is timing it is the last anti-Romney standing who could slay him—and that's Rick Santorum.

But perhaps there is an even greater, historic logic at work.

The Republican party, at least since its Ronald Reagan-era reconstitution, has cultivated its blood grievance against liberal values and lifestyle (in spite of Reagan's own personal lack of heart for this fight). Of the Republican party's two main themes – the other being anti-tax and anti-state control – the social fight has been the more animated and, arguably, the more heartfelt.

The true antagonism in the country is not about the administration of government, but about how we live, between new and evolving, and old and fixed standards of conduct. It's the most fundamental western debate: secular or not, reason or ritual.

It is hard to imagine a candidate who might more completely personify the God-driven, anti-scientific, father-centered, my-way-or-the-highway, throwback life than Rick Santorum. Even the most conservative politicians tend to live a pretty modern-world, yuppified life. Not Santorum. Part of his appeal, particularly against the ever-shifting and mollifying Romney, is that his shtick is real. Mind-blowing, but real. Not only does he have far more children than any modern, striving, trying-to-do-better American has, but he home-schools them. Home-schooling is one of those things I think most Americans understand: a true and arduous commitment, albeit one for weirdoes. You get it all with Santorum: the Christian nation; the traditional family; the sexual aversions (including one against contraception); the homemade theology.

It even seems likely that he wouldn't run from his primary-playing wedge campaign during the general election: what we're seeing now is what we'd probably get, no matter how cockamamie and dumbfounding.

In other words, this would be a campaign starkly pitting the two competing strands of American culture against each other. It's a remarkable opportunity: finally, a referendum on all things that have so upset the conservatives and have been so embraced by everybody else – abortion; gay marriage; sexual license; the new family (or non-family) life. How could it not be? These are Rick Santorum's issues, his reason for being here. This is the debate, however futile, he seems to believe God made him for.

But what if? Elections are like jury trials. The outcome is necessarily unpredictable. What if Europe goes over the abyss and with it the nascent US recovery? What if Israel goes after Iran and gas goes to eight bucks a gallon at the pump? What if the unforeseen happens, and President Obama fumbles his response?

Then … President Santorum? And a preposterous chapter in American history?

But then again, the compelling, if also train-wreck, aspect about Santorum is that it really does seem like he'd rather be right than be president. His wealthy Super Pac supporters seem similarly hell-bent (and rich enough not to need to worry about actually winning an election). No matter what happens and how much the Democrats might find themselves up against it, Santorum seems determined to make this an up-or-down vote for the way he is living and wants others to live, as opposed to the way most Americans have actually chosen to live.

That vote, by sheers numbers of people living by modern conventions, seems preordained.

The prospect of a defeat of this magnitude is obviously as horrifying to Republican leaders and stalwarts – all who seem to be lining up in a panicky defense of Romney – as Santorum's actual election would be to liberals. Although I'm not sure it should be. What happens to the Republicans after Romney tries to fashion a middling and, to conservatives, quisling general election position and is defeated (and who is expecting otherwise)? In four years, another round of eccentricity and exaggeration?

An up-or-down vote on far-out rightwing lifestyle prescriptions – is the country for or against, and what by what proportion?—is as good for the Republicans as for liberals. It marginalizes the margin.

Everybody has avoided this issue. The passion of the committed has been too great to face. They are a minority whose limited future has oddly fortified them.

So, finally, in a likely landslide of teachable-moment proportions, we can vote for how we want to live. That'll be a vote everybody will want to cast.