Tomorrow morning–after 16 months of stumping and speechifying, of dissing and debating, of Budweiser and Crown Royal and Change You Can either Believe In or Work For–the neverending battle for the Democratic nomination might finally, well, end.

Over Hillary Clinton’s dead body, that is.

In the two weeks since last they clashed in Pennsylvania, Clinton and rival Barack Obama have flooded Indiana and North Carolina with a flurry of spending and sparring that underscores the stakes in today’s twin primaries: for Clinton, it’s a matter of staying alive; for Obama, it’s all about sealing the deal. Speaking from the back of a red pickup truck, Clinton styled herself as a pugilistic working-class hero at ease questioning her opponent’s Second Amendment cred, pumping gas or comparing the Democratic race to, um, NASCAR; Obama countered with a series of low-key, stadium-free stops meant to show off his fresh-faced family—and his skills on the b-ball court. When Clinton seconded John McCain’s proposal for a summer gas-tax holiday, Obama (and every economist on Earth) accused her of pandering; Clinton fired back with a TV commercial claiming that she was only candidate in tune with the needs of average Americans, and the campaigns launched an escalating, multi-million dollar, 10-ad air war to make themselves heard. Behind the scenes, reporters were treated to a steady stream of invective from both sides–even as the candidates stayed relatively sunny on the stump.

So what should they expect in return? There are three possible outcomes—and none (sorry Obamaniacs!) will knock Clinton out of contention (even if one would slash her shot of winning from five percent to about one). Because Clinton has no chance of erasing Obama’s 145 pledged-delegate lead before the end of regulation–or, thanks to proportional allocation, of closing the gap significantly in Indiana and North Carolina (unless she wins by 20 percent margins statewide)–what matters most is not tonight’s tiny shifts in the delegate count or the popular-vote tally but how the uncommitted superdelegates (who will, after all, decide the race) interpret the broader results. The first—and most implausible—outcome is twin victories for the senator from New York. Indiana is seen as something of a toss-up, so a Clinton win there would surprise no one. But if Clinton can also come from behind in the Tar Heel State—where Obama’s 20-point head start and a Democratic electorate that’s 35-40 percent black make her a serious underdog—expect an avalanche of headlines about how badly the reemergence of Rev. Jeremiah Wright bruised Obama, how he failed (yet again) to win over working-class whites and, as a result, how the omnipotent superdelegates are now even warier than before. They may even start breaking for her.

The second—and likeliest—scenario is a split decision: Clinton in Indiana, Obama in North Carolina. This is precisely what the polling (which, despite all the hand-wringing, hasn’t been wrong since New Hampshire) predicts. If the margins match expectations—Clinton by five, Obama by eight, give or take—the commentariat will yawn. That may be bad news for Clinton, who needs a boost to slow the steady trickle of superdels to Obama—but it’s hardly deadly. As my colleague Richard Wolffe reports, “Obama is expected to finish the primary season roughly 100 shy of the 2,025 delegates needed to secure the nomination. Clinton will be around 250 short of the goal line… [or] roughly the number of superdelegates who remain undeclared. As a result, the Democrats face a twilight zone—in which Obama cannot collect enough superdelegates to secure the nomination, and Clinton runs out of bodies to close the gap.” A closer-than-expected second in Indiana for Obama—or a narrow N.C. silver for Clinton—will generate some positive coverage for the respective recipients. (The closer, the better.) But after today, only six primaries (and 217 pledged delegates) remain. A split decision of any sort, then, means that “the battle will shift from a grinding state-by-state slog for primary votes to an inside fight for the hearts and minds of a few hundred undeclared superdelegates”—and it will continue at least through June 3, if not the convention.

The final possibility? An Obama sweep. If the Illinois senator ekes out wins in Indiana and North Carolina, the race is essentially over. Not only would an Obama twofer refute Clinton’s central rationale for remaining in the race—you know, that superdelegates should side with her because Rev. Wright and Bittergate have destroyed Obama’s electability—but it would also give those same party poobahs the political cover they need to break decisively for the pledged-delegate and popular vote leader. According to a recent report in the Politico, the 80 uncommitted Congressional superdelegates have already secretly sided with a candidate—most of them Obama—and are merely waiting for the right moment to go public. This would be that moment.

Regardless of what happens tonight, Clinton will keep fighting. Her persistence is due in part to the next states on the schedule: West Virginia on May 13 and Kentucky on May 20. If Clinton wakes up tomorrow with at least one win under her belt, this duo of white, working-class, largely Appalachian states will likely keep her streak alive; she leads 56-27 in the latest West Virginia survey and 62-28 in the most recent sounding from Kentucky. Since late March, Bill Clinton has been sneaking off to the Mountain and Bluegrass States for a series of appearances in places like Frankfort, Maysville, Beckley and Parkersburg—about a dozen in all.

That said, the crucial states for Clinton are no longer on the schedule: Florida and Michigan. “I have no intention of stopping until we finish what we started and until we see what happens in the next 10 contests and until we resolve Florida and Michigan,” said Hillary in March. “And if we don’t resolve it, we’ll resolve it at the convention – that’s what credentials committees are for.” As if to underscore her determination, the Clinton campaign yesterday changed on its website the number of delegates needed to win the nomination from 2,025 (the DNC’s official threshold, which doesn’t include Florida and Michigan) to 2,208 (which does). “That’s what we believe is the standard for deciding this,” said top Clinton strategist Geoff Garin. “Who has the majority of the total delegates including Michigan and Florida.” If the Garin and Co. stick to their guns, they’ll keep campaigning even if Obama sweeps today and eventually hits the 2,025 mark; their last best hope is a close finish in the estimated popular vote, which they believe would delegitimize Obama’s inevitable pledged-delegate victory. Clinton needs Florida and Michigan to make that case. Which means, in the end, that North Carolina, Indiana, West Virginia, Kentucky, Oregon, Puerto Rico, South Dakota and Montana may not matter nearly as much as May 31, when some 30 party hacks on the DNC’s rules committee meet to decide whether to count those two renegade states. Mark your calendars. That’s the first day this grueling Democratic deathmatch could finally end.

Until then, the wait goes on.