WASHINGTON, D.C. -- Even before Sen. Barack Obama won his ninth-straight contest against Sen. Hillary Clinton in Wisconsin last Tuesday, wise old heads in the Democratic Party were asking this question: Who will tell her that it's over, that she cannot win the presidential nomination and the sooner she leaves the race the more it will improve chances of defeating Sen. John McCain in November?

In an ideal though unattainable world, Clinton would have dropped out when it became clear even before Wisconsin that she could not be nominated. The nightmare scenario was that she would win in Wisconsin, claiming a "comeback" that would propel her to narrow victories in Texas and Ohio March 4. That still would not cut her a path to the nomination. Telling her then to end her candidacy and avoid a bloody battle stretching to the party's Denver national convention might not be achievable.

The Democratic dilemma recalls the Republican problem, in a much different context, 34 years ago, when GOP graybeards asked: "Who will bell the cat?" -- go to Richard M. Nixon and inform him he had lost his support in the party and must resign the presidency. Sen. Barry Goldwater successfully performed that mission in 1974, but there is no Goldwater facsimile in today's Democratic Party (except for Sen. Ted Kennedy, who could not do it because he has endorsed Obama).

Clinton's rationale for remaining a candidate is the Texas-Ohio parlay on March 4, with pre-Wisconsin polls giving her a comfortable lead in both states. But Texas has become a dead heat, and her Ohio margin is down to single digits. Gov. Ted Strickland, Clinton's leading endorser in Ohio, is reported following the Wisconsin returns to privately have expressed concern as to whether he could hold the state for her in the ensuing two weeks. If she ekes out a win in Ohio while losing Texas, who then will bell Hillary?

The inevitability of Clinton becoming the first female president was based on her dominance over weak fields in both parties. McCain was the one Republican who worried Democratic strategists, and he appeared dead three months ago. Mitt Romney, the then-likely Republican nominee, was viewed in Democratic circles as unelectable.

Obama's improbable candidacy always worried Clinton insiders, which explains the whispering campaign that the Illinois neophyte would prove vulnerable to Republican onslaught as the presidential nominee. That private assault continues to this day, with Obama described as a latter-day George McGovern whose career record of radical positions will prove easy prey for GOP attack dogs.

But Clinton could not go before Democratic primary voters and assail Obama for being too far to the left. Instead, she insinuated moral turpitude by asserting that Obama had not been "vetted." When that backfired, she claimed plagiarism by Obama in lifting a paragraph from a speech by his friend and supporter Massachusetts Gov. Deval Patrick -- an approach that yielded mainly derisive laughter among politicians.

I listened in on last Wednesday's news media conference calls by Clinton campaign managers Mark Penn and Harold Ickes in the wake of her Wisconsin drubbing. Incredibly, they were hawking the same plagiarism charge that had proved ineffective. Clinton herself raised the bogus issue again in Thursday night's debate from Austin and was rewarded with boos from the Democratic audience.

Clinton's burden is not only Obama's charisma but also McCain's resurrection. Some of the same Democrats who short months ago were heralding her as the "perfect" candidate now call her a sure loser against McCain, saying she would do the party a favor by just leaving.

Clinton's tipping point may have come when it was announced that her $5 million loan to her campaign came from a joint fund she shares evenly with Bill Clinton. That puts into play for the general election business deals by the former president that had transformed him from an indigent to a multimillionaire and excite interest in their income tax returns, which the Clintons refuse to reveal. The prospect impels many Democratic insiders to pray for clear Obama victories on March 4 that they hope will make it unnecessary for anybody to beg Hillary Clinton to end her failed campaign.