It didn’t take long to set the tone at last night’s Democratic Debate in Cleveland, Ohio.

Senators Hillary Clinton and Barack Obama opened what many are calling the most contentious debate yet with a particularly heated exchange over the candidates’ respective health care plans.

Ignoring the intervention of moderator Brian Williams, Clinton and Obama dueled an incredible 16 minutes on the subject, the major points of disagreement being Clinton’s contention that Obama’s plan would not cover everyone, and, conversely, Obama’s contention that Clinton’s plan would force people to buy insurance, even if they didn’t want it or couldn’t afford it.

Like much of the rest of the debate, relatively little was resolved despite tense, at times aggressive, accusation and questioning.

Early in the debate, Clinton expressed resentment at what she called the recently “disturbing” tactics of Obama, including mailings on health care and NAFTA she argued were false and unsubstantiated. Clinton further cited the recent episode of “Saturday Night Live” as yet another example of what her campaign has decried as an unfair and unbalanced media.

The line drew hisses and groans from an otherwise mostly passive audience.

At another point - a victory for Clinton, if only regarding syntax - the audience cheered as Obama rather grudgingly agreed to “reject” rather than “denounce” the support of Louis Farrakhan - the leader of the Nation of Islam, who recently pledged his support of Obama, but is a vocal anti-Semite and opponent of Israel. Obama previously did make it clear that he did not formally seek Farrakhan’s support and that he strongly denounced the leader’s “inappropriate and unacceptable” anti-Semitism.

The end of the debate yet again struck a sentimental tone for both candidates, as both Clinton and Obama declared their respect for the other, and pledged to work to put a Democrat in the White House no matter the nominee. Although last night’s debate was marked largely by contention and controversy, the final moments found the candidates in an almost foreign state of passivity and, indeed, resignation - to the fate of March 4, and the looming battle beyond.

In what was perhaps the evening’s most poignant moment, the candidates were asked to reflect upon their experience in public service and describe a mistake they had made or a vote they had cast which they now regret. Senator Clinton spoke of the Iraq war and her vote to authorize it with unusual candor, offering not an outright apology, but nonetheless speaking with a definite, subdued sadness. Senator Obama spoke of the case of the incapacitated and severely brain-injured patient Terry Schiavo, whose husband believed should have her feeding tube removed based on clinical evidence that recovery was unlikely, if not impossible. Obama said the U.S. Congress’ unanimous decision to intervene in the case broke a boundary it should have never crossed, and expressed embarrassment and disappointment in himself for not speaking out.