STRONG GIRLS VOTE MCCAIN-PALIN read the white block letters on the baby’s pink onesie, and her mother was chanting “Sarah! Sarah! Sarah!” on a gorgeous morning in Van Dyke Park in Fairfax, Virginia. They were two in a crowd of 15,000—a number, oh, 50 to 100 times greater than the norm for a John McCain event pre-Palin—who’d turned out for the final joint appearance of the Republican ticketmates before they temporarily went their separate ways last week. Up onstage, Sarah Palin was perched atop a pair of ruby-red heels, which seemed appropriate. Maureen Dowd may see the Alaska governor as Eliza Doolittle, but she strikes me more as Dorothy: the girl swept up in the tornado, lifted suddenly out of her black-and-white world, deposited in a Technicolor Oz.

Certainly Barack Obama and his campaign must feel as if a house has dropped on their heads. And certainly the men behind the curtain in McCain-land have done their best to enhance the pain. The pummeling has come hard and fast: accusations of sexism against Obama, Joe Biden, and their Democratic allies; contentions that Obama favors “comprehensive” sex education for kindergartners; visual allusions to the Democrats as a pack of wolves keen to prey on lovely Sarah; and, lest we forget, condemnations of the hopemonger for purportedly comparing Palin to a gussied-up porcine pretender.

All those charges were leveled in the span of 24 hours last week. It was an ugly, low, ludicrous moment, in which the howls of faux Republican outrage (“offensive,” “disgusting,” “desperate,” “disgraceful”) were deafening and the river of crocodile tears so profuse that FEMA nearly had to be called in. But it was also undeniably tactically effective, knocking Obama off-balance and off-message, getting inside his head, luring him into a losing shadow-boxing match with the Palin phenomenon rather a real fight with his real adversary—you know, um, that guy McCain.

Yet the lipstick wars were about more than tactical skirmishing to win a couple of news cycles. They were a sign that, in picking Palin as his V.P., McCain had introduced into the electoral equation a set of variables—gender, class, celebrity, ideology—at once powerful, combustible, and unpredictable. They presaged a fall campaign in which the most wretched sort of identity politics will apparently prevail. And they reflected a new strategic dynamic that may well determine the outcome: the fierce and frantic pursuit by both sides of this year’s “It” demographic, the so-called Wal-Mart moms.

Coming across as one of those moms has been the genius of Palin’s performance in her two weeks on the national stage. The biography, the family, the plainspokenness, the spunkiness, the overarching Mary Tyler Mooreness: All of it has shifted focus away from more awkward and pertinent questions. About her qualifications and readiness to become commander-in-chief. About her gubernatorial record. About the falsehoods she is brazenly peddling about her stance on the Bridge to Nowhere. About the inconsistencies between her image as an anti-earmark reformer and her history of scarfing down so much trayf that she’s at risk of trichinosis.

What we do know about Palin is that, at least for now, she has jolted the race in a way that makes her selection by McCain seem like something it was not: a carefully wrought, exquisitely calibrated maneuver. The effect of her arrival in the mix has been evident and advantageous to her boss in every national post-GOP convention poll. And it’s been particularly salutary in one area above all: McCain’s support from white female voters. According to last week’s ABC/Washington Post poll, McCain’s standing among them has improved by twenty points (from 50-42 behind to 53-41 ahead) since teaming with Palin. The numbers from the latest NBC/Wall Street Journal survey are less gaudy, to be sure, but still nothing to sneeze at: an eleven-point shift, from one point down to ten ahead.

Just how important is the XX-chromosome Caucasian demo? Incredibly, in a word. White women are quintessential swing voters, pragmatic, independent, with weak party allegiances and a tendency to break late. In 1996, with the help of those fabled “soccer moms,” Clinton carried the demo by five points and won the election by 8.5 in spite of losing the white-male vote by eleven. In 2004, George W. Bush’s appeal to “security moms” enabled him to carry white women by eleven, which made all the difference between losing the popular vote in 2000 and winning the next time around.

Among strategists and pollsters it’s the Wal-Mart moms—slightly older and more downscale than their predecessors, more culturally conservative and more attuned to economics—who look most like the pivotal swing-voting bloc in 2008. Mark Penn, Hillary Clinton’s erstwhile chief strategist and father of the soccer-mom coinage, goes so far as to write, “[White] women 30 and older, all the way up to age 85, will likely decide the election.”

That Palin has stirred enthusiasm, or at least curiosity, in this group comes as no surprise. But among the Washington wise guys and gals the conventional wisdom is that, over time, her impact will diminish. Back in 1984, as both the Democratic pollster Celinda Lake and the former Bush operative Matthew Dowd have pointed out, the placement of Geraldine Ferraro on the Democratic ticket occasioned a Palin-size bounce on behalf of Walter Mondale. And we all know how that turned out.

But Palin may turn out to be a more culturally resonant figure than Ferraro ever was. “The reason she appeals to women—and not just working-class women, but most women other than elite women—is that she represents something that they like to see in themselves: strength, authenticity, character,” says Democratic strategist Gigi Georges of the Glover Park Group. “She represents an attitude of ‘I don’t really care what anyone thinks. What the media thinks. What the elites think. I just don’t give a damn.’ And plays not just to small-town America but to all women who feel they’ve faced something in their lives, that they’ve been put down, not recognized for their intelligence, not recognized for their character. And there she is—she’s just like them.”

This is a kind of connection that Obama has never forged among the Wal-Mart moms—and Palin’s electrifying appearance on the scene may provide them an excuse for rejecting a candidate they never warmed to in the first place. “For some white, working-class voters who don’t want to vote for Barack Obama but weren’t sure about McCain, Palin gave them a good reason to take another look and consider supporting McCain,” the veteran Democratic organizer Steve Rosenthal told Politico. “On the one hand, it could be a temporary reshuffling of the deck. And on the other hand, it underscores the deep-seated problems we have in this race with race, class, and culture.”

Those problems, of course, are precisely the ones that the McCain campaign has always planned to exploit against Obama. And with Palin having provided an impetus for white women to give McCain a second gander, his chief strategist, Steve Schmidt, is wasting no time driving the message that Obama is scary, dangerous, a clear and present threat to their children. The ad the campaign released last week on Obama’s supposed support of sex-ed for 5-year-olds—which stands as one of the most scurrilous, baseless, racially loaded pieces of fearmongering since Willie Horton—is a classic of the genre. Expect more of the same in the days ahead, focusing on crime: that Obama was soft on gangs, sex offenders, and drug addicts when he was in the Illinois State Senate.

In the face of such attacks, Obama will confront an uphill fight in securing the support he needs to win of the Wal-Mart moms. The standard Democratic advice, which the Obama campaign appears to be attempting to embrace, is for Obama to change the subject to economics: to kitchen-table matters where what he’s offering is a clear alternative to the policies promulgated by Bush and endorsed by McCain. One trouble here is that Obama has yet to put forward anything resembling a coherent economic narrative that makes sense of the hardship the Wal-Mart moms and others are going through. But another is simply the novelty and attractiveness of Palin.

“Her appeal is such an emotional appeal, I just don’t think issues matter much,” says Georges. “The McCain people have used her to turn Obama into the conventional politician. If you can step away from it and not be partisan, you just have to admit that it’s an incredibly neat trick, one of the cleverest things I’ve seen in my time in politics. If she doesn’t screw up, I really think she becomes transformative.”

That, it should be said, is an exceedingly big if—and one that’s looking iffier all the time. Her maiden interviews at the end of last week with ABC’s Charlie Gibson made clear that, on matters of substance, Palin is wildly out of her depth. Her answers regarding the Bush doctrine of preemption had a deer-in-the-headlights quality that called to mind Dan Quayle, and her discussion of foreign policy more generally was thin and shaky, a recitation of hastily memorized talking points. She said nothing disqualifying but also did nothing to allay doubts about her readiness. Former Republican senator Lincoln Chafee recently referred to Palin as a “cocky wacko”; in her worst moments with Gibson, you could begin to understand why.

The question is whether all this will sink in with voters—or be overwhelmed by her celebrification. The irony here is that, in no small way, Obama made Palin possible. The celebrity status of politicians is nothing new, but Obama took it to another level. He created an atmosphere where a paper-thin résumé was no longer seen as an obstacle to success but an asset. He built his campaign around a promise of change that even his adherents will grudgingly admit was more atmospheric than substantive. As a wise man observed the other day in a slightly different context, “We do not get to choose who follows through the doors we open.” Or how fast they come charging in—or what they do when they get there.

E-mail: jheilemann@gmail.com.