But surely, it could be argued, the mud in the Democratic race will be as much a drag on that party’s eventual nominee as the incumbent president is on the G.O.P. ticket. The counterargument, advanced by Mrs. Clinton in justifying her “kitchen sink” attacks on Mr. Obama, is that the Democrats are better off being tested now by raising all the issues the Republicans will. It’s a fair point. The Wright, Rezko, Ayers, “bittergate” and flag-pin firestorms will all be revived by the opposition come fall. Voters should indeed see how Mr. Obama deals with them, just as Democrats also need to gauge how the flash points of race and gender will play out in the crunch.

The flaw in Mrs. Clinton’s refrain is her claim that she, unlike her challenger, has already been so fully vetted that her candidacy can offer no more unpleasant surprises. “I have a lot of baggage, and everybody has rummaged through it for years,” she says. Perhaps the delusion that she has a get-out-of-scandal-free card comes from her unexpected endorsement from Richard Mellon Scaife, the nutty Pittsburgh newspaper publisher who once spent a fortune trying to implicate the Clintons in the “murder” of Vince Foster. Or perhaps she thinks Fox News will call off the dogs now that her campaign chairman, Terry McAuliffe, is appearing in network promos endorsing its “fair and balanced” shtick.

But the incessant praise for Mrs. Clinton’s resilience as a candidate by Karl Rove, Pat Buchanan and William Bennett reveals just how eager they are to take her on. The dealings of the Bill Clinton post-presidency, barely alluded to by Mr. Obama in his own halting bouts of negative campaigning, have simply been put on hold while the Democrats slug it out. Close observers of The Wall Street Journal, The New York Post and Fox News can already read Rupert Murdoch’s tea leaves, and not just those from China. “Clinton Foundation Secrets” was the title of The Journal’s lead editorial on Friday profiling a rogues’ gallery of shady donors.

Mrs. Clinton’s supporters would argue that she’s so battle-tested she could fend it all off. She’s unlikely to get the chance. For all the nail-biting suspense being ginned up, the probable denouement remains unchanged. When the primary juggernaut finally ends  following picturesque day trips to Puerto Rico and Guam  the superdelegates will likely succumb to the math of Mr. Obama’s virtually insurmountable pledged-delegate total.

Image Credit... Barry Blitt

There’s also a way that two super-superdelegates, the duo on the Democrats’ last winning ticket, could trigger a faster finale. Bill Clinton could do so by undermining his wife once more with another ill-timed, red-faced eruption. Al Gore could possibly do so with a well-timed endorsement before his party gets mired in yet another Florida recount.

There’s only one way this can end badly, no matter how long it lasts. That would be if the loser, whoever it is, turns sore and fails to rally his or her troops around the winner. It’s all about “the way the loser loses,” as the Illinois Congressman Rahm Emanuel, who is neutral in the race, likes to say. While the Clintons are capable of such kamikaze narcissism, their selfish desire to preserve their own political future, if not the party’s, may be a powerful check on those impulses.