RENEE MONTAGNE, HOST:
And when it comes to American politics, Democratic presidential candidates Hillary Clinton, Bernie Sanders and Martin O'Malley clashed last night. This time in an NBC News debate in Charleston, S.C. As Mara Liasson reports, the exchanges were sharper and more intense because the race has changed.
MARA LIASSON, BYLINE: In the first three debates Hillary Clinton practically ignored Bernie Sanders. But she threw that approach out the window last night in an effort to stop his momentum. Sanders is threatening to erase Clinton's lead in key early states, a fact he was happy to point out when asked by the NBC moderators why he's still trailed Clinton by 2 to 1 among African-American voters.
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BERNIE SANDERS: As Sec. Clinton well knows, when this campaign began she was 50 points ahead of me. We were all of three percentage points. Guess what? In Iowa, New Hampshire, the race is very, very close. Maybe we're ahead in New Hampshire.
LIASSON: And Sanders said he's even beating Donald Trump in some of the hypothetical general election polls.
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SANDERS: To answer your question, when the African-American community becomes familiar with my Congressional record and with our agenda and with our views on the economy and criminal justice, just as the general population has become more supportive, so will the African-American community, so will the Latino community.
LIASSON: Not if Hillary Clinton can help it. She was on offense last night tearing into Sanders on health care, taxes and guns. The debate was just a few blocks from the church where a mass shooting last year left nine worshipers dead.
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HILLARY CLINTON: I have made it clear, based on Sen. Sanders' own record, that he has voted with the NRA, with the gun lobby numerous, times. He voted against the Brady Bill five times. He voted for what we call the Charleston loophole. He voted for immunity from gun makers and sellers, which the NRA said was the most important piece of gun legislation in 20 years.
LIASSON: Sanders defended himself but never explained why just this week he reversed himself on immunity for gun makers.
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SANDERS: Well, I think Sec. Clinton knows that what she says is very disingenuous. I have a D-minus voting record from the NRA.
LIASSON: The Clinton campaign had tried all week to put Sanders on the defensive for not explaining how he would pay for the single-payer health care plan he wants to put in place of Obamacare. Two hours before the debate last night, Sanders' campaign released some details - new taxes on employers, households and a hike in income taxes. Sanders admitted some middle-class families would be paying slightly more in taxes, but...
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SANDERS: It's one thing to say I'm raising taxes. It's another thing to say that we are doing away with private health insurance premiums. So if I save you $10,000 in private health insurance and you pay a little bit more in taxes, in total, there are huge savings in what your family is spending.
LIASSON: A single-payer-Medicare-for-all plan is still very popular with the Democratic base. But Clinton pointed out that Sanders' plan couldn't get support in a Democratic Congress.
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CLINTON: And even during the Affordable Care Act debate, there was an opportunity to vote for what was called the public option. In other words, people could buy in to Medicare. And even when the Democrats were in charge of the Congress, we couldn't get the votes for that. So what I'm saying is really simple. This has been the fight of the Democratic Party for decades. We have the Affordable Care Act. Let's make it work.
LIASSON: For his part, Sanders stuck to his stump speech attacks on billionaires, big banks and the campaign-finance system. He repeatedly called for a political revolution. And with some backup from Martin O'Malley, who also took part in the debate, Sanders portrayed Clinton as part of the system he wants to overthrow. He attacked her for taking $600,000 in speaking fees from Goldman Sachs. Clinton defended herself by invoking Obama, who is very popular with Democrats and nowhere more so than in South Carolina, where the majority of Democratic primary voters are African-American.
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CLINTON: He has criticized President Obama for taking donations from Wall Street. And President Obama has led our country out of the great recession. Sen. Sanders called him weak, disappointing. He even, in 2011, publicly sought someone to run in a primary against President Obama. So I'm going to defend President Obama for taking on Wall Street.
LIASSON: Democratic voters are attracted to Sanders' passionate calls to change the status quo. But Clinton is hoping they also care about preserving President Obama's legacy and that she is the candidate tough enough and pragmatic enough to do that. This was the Democrats' last debate before voters go to the polls in Iowa and New Hampshire. A Sanders victory in both states could change the dynamic of the race in other places where Clinton currently has a big lead, like South Carolina. Mara Liasson, NPR News, Charleston. Transcript provided by NPR, Copyright NPR.