Sen. Bernie Sanders and former Secretary of State Hillary Clinton spar during a Democratic presidential primary debate hosted by MSNBC at the University of New Hampshire on Thursday.
Former Maryland Gov. Martin O'Malley, Sen. Bernie Sanders, I-Vt. and Hillary Clinton at the NBC News-YouTube Democratic presidential debate at the Gaillard Center on Sunday in Charleston, S.C.
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Democratic presidential candidates Bernie Sanders, Hillary Clinton and Martin O'Malley stand on the stage prior to Saturday's Democratic primary presidential debate in Des Moines, Iowa.
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