MILWAUKEE (CN) - Sparks flew Thursday night in Milwaukee as Hillary Clinton and Bernie Sanders argued about Wall Street money and its influence on politics, realism and idealism, and the record of the man who holds the office both of them want.
Both candidates called for criminal justice reform, as the debate opened with domestic issues. Wisconsin has the highest incarceration rate of black men in the nation, and the highest unemployment rate of African-Americans.
The first clash came on health care.
Sanders wants a single-payer system, as in England and France, an approach Clinton said would throw out the hard work and effectiveness achieved by Obamacare.
"Having been in the trenches, fighting for this ... the last thing we need is to throw our country into a contentious debate about health care again," Clinton said.
She said she preferred working toward full enrollment under Obamacare rather than "trying to start all over again, gridlocking our system and trying to move on from zero."
Clinton then repeated her oft-made criticism of Sanders: that though they may agree on principle, he stands little chance of enacting his programs, due to the realities of politics.
Sanders replied with his customary political ammo: that the country can rebuild our deteriorating infrastructure by taxing corporations' offshore accounts and imposing a small, but lucrative transaction tax on Wall Street. (With more than 1 billion stock trades a day, a penny tax per transaction would raise more than $10 million a day.)
"We bailed them out, now it is their time to help the middle class," Sanders said.
Clinton called Sanders' proposal for tuition-free college unrealistic, saying it would need support from the nation's governors, including Wisconsin Gov. Scott Walker, who has supported cuts to higher education.
"I'm a little skeptical that your governor actually cares enough about higher education to make any kind of commitment like that," Clinton told the hometown crowd to loud applause.
Both candidates said the nation has a long way to go toward racial equality.
Sanders called Wisconsin's racially unbalanced prosecution and sentencing policies an "unspeakable tragedy." Clinton agreed, citing the fatal police shooting of Dontre Hamilton, an unarmed, mentally ill black man in a Milwaukee public park in 2014.
After quibbling about voting records and immigration reform, things heated up when questions returned to what Sanders calls America's "corrupt" campaign finance system.
When Clinton assured the audience that donors will not influence her decisions, Sanders replied: "Let's not insult the intelligence of the American people."
"People are not dumb," he added. "Why in God's name does Wall Street make huge campaign contributions? I guess just for the fun of it, they throw money around?"
Sanders told the audience that his individual supporters - who made up the lion's share of the crowds, braving the frigid temperatures to show their support with signs and chants - have provided all his campaign funding without the need for a super PAC.
His average campaign contribution is $27, he added.
When questions turned to foreign relations, both candidates roundly condemned anti-Muslim comments by Donald Trump and other Republican candidates. Trump, and others, have called for an end to granting refugee status to Muslims.
Sanders blasted Clinton for citing former Secretary of State Henry Kissinger as a mentor, saying his "destructive" actions allowed the Khmer Rouge to massacre millions of Cambodians.
Taking politics to a personal level, Sanders added: "I am proud to say that Henry Kissinger is not my friend."
Clinton, citing Sanders' relative lack of foreign policy experience, asked whom he would consult for foreign policy advice.
"It ain't Kissinger," Sanders responded.
When asked what American leaders they admired, both candidates named President Franklin Delano Roosevelt.
And foreign leaders? Sanders chose Winston Churchill; Clinton, Nelson Mandela.
Clinton then lit into Sanders for his criticism of President Barack Obama. Saying that the Vermont senator has called the president "weak," Clinton said she expected this from Republicans, but not from a man who hoped to succeed Obama in office.
"That is a low blow," Sanders replied, calling the president a friend whom he has supported on many issues.
"Last I heard, we live in a democratic society," Sanders said. "Last I heard, a United States senator had the right to disagree with the president, including a president who has done such an extraordinary job."
When Clinton refused to back down, Sanders returned fire: "One of us ran against Obama. I was not that candidate."
Sanders closed by calling Americans to participate in the electoral process, saying that neither he nor Clinton could effect change on their own.
Clinton ended with a jab at Sanders' focus on income inequality and Wall Street regulations.
"I am not a single-issue candidate, and I do not believe we live in a single-issue country," she said.
The two-hour debate at the University of Wisconsin-Milwaukee, hosted by PBS NewsHour and moderated by news anchors Gwen Ifill and Judy Woodruff, was interspersed with questions from Facebook users.
Press reactions to the debate early Friday morning seemed to track the conventional wisdom of the unexpectedly energetic Democratic campaign: that Clinton impresses with her mastery of issues, though has not been able to stir up excitement from the grass roots, as Sanders has done.
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