CHARLESTON, SC - JANUARY 17:  Democratic presidential candidates Martin OMalley (L), Hillary Clinton (C) and Senator Bernie Sanders (I-VT) participate in the Democratic Candidates Debate hosted by NBC News and YouTube on January 17, 2016 in Charleston, South Carolina. This is the final debate for the Democratic candidates before the Iowa caucuses.  (Photo by Andrew Burton/Getty Images)
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CHARLESTON, SC - JANUARY 17: Democratic presidential candidates Martin OMalley (L), Hillary Clinton (C) and Senator Bernie Sanders (I-VT) participate in the Democratic Candidates Debate hosted by NBC News and YouTube on January 17, 2016 in Charleston, South Carolina. This is the final debate for the Democratic candidates before the Iowa caucuses. (Photo by Andrew Burton/Getty Images)
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