There is something about the purported emotional complexion of the American South, something about a deep pool of dark and febrile passions only hinted at beneath the surface veneer of sunny optimism and quaint codes of genteel civility, that wields a powerful--and peculiarly positive--grip on the Northern imagination. It is present in the literary world, of course, where cosmopolitan intellectuals in New York salons have long swooned like heatstroke-stricken plantation ladies for Southern writers delivering a romanticized vision of mossy-bayous-and-mint-juleps exoticism, where the sun's heat is matched only by the fireworks unleashed by oversized personalities and the slow peat burn of sublimated sexuality.

And it is an omnipresent feature of the political world as well. Which brings me to John Edwards, and why John Kerry should choose him as a running mate. How else to explain the amazing success of North Carolina's John Edwards in the Northern primaries? How else to explain the reception he received recently at Patty Murray's annual Golden Tennis Shoe fundraiser, where the upscale Seattle liberals that form the support base of the senior senator from Washington rewarded the pro-Iraq War Southern centrist with repeated and heartfelt standing ovations?

John Kerry will soon be facing the first big test of his general election campaign: the selection of his running mate. If he is smart, he will pick Edwards. But not for the conventional reason, that balancing the ticket geographically with a Southerner will put the South in play for the Democrats. With a few important exceptions (Florida), the South is lost to the Democrats. Kerry is reported to be skeptical of Edwards' drawing power in the South. He is right--Edwards may not help Kerry at all below the Mason-Dixon Line. Edwards was trounced by Kerry in his own home region, losing Virginia, and Tennessee to his Boston Brahmin rival (he won his home state, North Carolina, well after the nomination had already been decided).

Kerry should pick Edwards for the most counterintuitive of reasons: because Edwards will help him in the North, particularly in the closely divided Midwestern swing states where the election will be decided.

In Iowa, which kicked off the primary season on January 19, the most surprising story was not Howard Dean's collapse or John Kerry's surge to victory--there were signs of both in the preceding week or two--but Edwards' shockingly strong out-of-nowhere second-place finish. He took 32 percent, within spitting distance of Kerry's 36 percent, despite lacking a significant field organization in a caucus state where organization trades at a premium (unlike Kerry, who boasted a brilliant organizational machine). While his stealthy success was largely drowned out in the hysteria over Dean's infamous scream, Edwards' Iowa triumph made the eyes of the political cognoscenti pop in wonder.

And then Wisconsin, on February 17. Kerry had huge momentum after a close-to-perfect string of early wins; the polls predicted an easy victory. Election night turned into a near nail-biter, however, as early tallies showed Kerry and Edwards neck and neck. The final result: Kerry 40, Edwards 34.

Edwards has immense and underappreciated drawing power outside his Southern base. The more such voters see him, the more they like him. His early candidacy was predicated on little more than the fact that 45-year-old suburban women think he's dreamy. A little star power never hurts. But Edwards has become far more substantive since, and his Two Americas critique of Bush Republicanism--the division of the nation into a world of elitist privilege for the wealthy, and a world of anxiety and struggle for everyone else--resonates powerfully with the middle class.

But it's his huggy, I-feel-your-pain posturing that is his trump card. It was evident during his Seattle speech, as he made Murray and Maria Cantwell (both of whom spoke before him) look like rank amateurs. There is, it's true, a bit of the snake-oil salesman about John Edwards. But what jaded Northerners see as the worst sort of smarmy artifice when coming from a local politician, they read as roguish charm in a Southerner.

The Kerry campaign has so far been unable to electrify the Democratic electorate. But Edwards has that 1,000-volt smile, that hypnotic, you-mean-everything-to-me stare. And if that makes him appear a bit slick, well, y'all know that never hurt Bill Clinton none.