Putting aside Barack Obama's insurmountable lead in pledged delegates and Hillary Clinton's dubious claim that she leads in the popular vote (if Florida and Michigan are counted), there is a more urgent rationale -- beyond either candidate's math -- why superdelegates should line up behind Obama now.

Hillary, as part of the charismatic Clinton brand and a spirited fighter in her own right, may represent the heart of the Democratic Party, but it's clear that Obama's candidacy embodies the soul of the party.

Both Clinton and Obama recognize that change is desperately needed after the Bush administration's seven long years of abuses, blunders and lies. In less than two terms, the GOP has wrought disaster on the nation's security and economy under a set of failed policies that Republican candidate John McCain still subscribes to and defends. While either Democrat will fight McCain on the issues, they also will have to defend against personal attacks.

The Battle Royale this fall will decide more than just who wins the most electoral votes or has the longest coat tails for congressional seats. This presidential election will decide how the country feels about the vitriol and divisiveness that pervades politics. The outcome will either validate or repudiate a host of GOP policies: the nation's declining health care system and academic test scores, the country's fading standard of living, the Bush-McCain doctrine of elective war, the promotion of torture, and the manipulative incitement to fear (now conveniently color-coded in shades of yellow and red, not to mention black and white.)

Certainly, Clinton stands essentially on the correct side of most of these issues, though her vote for the use of force in Iraq shows horrendous foreign policy judgment, if not cynical political miscalculation. And her campaign of conflating racial divisiveness with fear of terrorism is both an adoption of, and inspiration for, the GOP's fall playbook.

Obama's downside for superdelegates boils down to being a black man in a country that Pennsylvania exit polls have shown is still tainted by racism. But that predicament is also precisely why the party must ultimately select him as its nominee.

This election is nothing less than a battle for the soul of the party and of the country. In addition to the other principles that a Democratic nominee should stand for and defend, there are some values at stake in this election that aren't part of Hillary's strategy. The core principles of racial tolerance, religious tolerance, governance by hope rather than through fear, and the use of war as a last resort, to name only a few. These values also are at the core of what it means to be a Democrat.

Yet more importantly now for superdelegates to consider (indeed, as some have already noted in their endorsements), these same principle also are fated to reside exclusively at the core of Barack Obama's candidacy. His fight, not hers, includes battling racism (and to emphasize the difference, the GOP has not attacked on Hillary's gender). His fight alone is against those who would paint Rev. Wright as unpatriotic or extreme. His fight alone is against guilt by association coupled with the fear of terror.

Certainly the GOP will continue to attack Obama on these fronts, just as they will attack Hillary on old issues like Whitewater, the Clinton ambivalence with the truth, and the sexual history of her husband. But surely Hillary's perceived weaknesses don't constitute core principles of the Democratic Party. The attacks on Obama, by contrast, sound a call to battle for all Democrats.

If it's going to be a fight for the country's soul, Democrats must first locate their own before they engage the enemy.