Democratic presidential candidate Hillary Clinton and her husband, former President Bill Clinton, speak at a "Get Out The Vote Rally" in Columbia, S.C., on Friday. Gerald Herbert/AP hide caption

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Director Spike Lee, in a radio ad released Tuesday endorsing Bernie Sanders says the Vermont Senator will "do the right thing" when he's in the White House. Axel Schmidt/AP hide caption

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Republican presidential candidate Donald Trump speaks at his election night party February 20, 2016 in Spartanburg, South Carolina. The New York businessman won the first southern primary decisively. Spencer Platt/Getty Images hide caption

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Republican presidential candidate, Sen. Marco Rubio, R-Fla., raises his arm with Gov. Nikki Haley and Sen. Tim Scott, R-S.C., during a town hall Thursday in Greenville, S.C. Paul Sancya/AP hide caption

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Barbie Byrd, of Columbia, S.C., joins a group of demonstrators on the grounds of the South Carolina State House calling for the Confederate battle flag to remain on the Capitol grounds in June 2015. Win McNamee/Getty Images hide caption

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Confederate flag radio ad/robo call

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Republican presidential candidates at the final GOP before the South Carolina primary on Saturday at the Peace Center in Greenville, S.C. Spencer Platt/Getty Images hide caption

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An attendee wears a Hillary Clinton campaign sticker at a rally in Columbia, S.C., last month. Young voters in Iowa and New Hampshire have helped fuel Bernie Sanders' candidacy, but as the race moves to South Carolina, a lot could change. Bloomberg/Bloomberg via Getty Images hide caption

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In South Carolina, Young Black Voters Could Put Holes In Clinton's Firewall

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S.C. State Rep. Mike Pitts, seen during last summer's debate over removing the Confederate battle flag from the State House grounds, has introduced a bill called the South Carolina Responsible Journalism Registry Law. John Bazemore/AP hide caption

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Russell Moore, president of the Southern Baptist Convention's Ethics and Religious Liberty Commission, said Donald Trump's "reckless, demagogic rhetoric" was an affront to religious freedom. Mark Humphrey/AP hide caption

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Democratic presidential candidate Hillary Clinton responds to a question from Roland Martin, host of TV One's News One Now, during a town hall meeting at Claflin University in Orangeburg, S.C., Richard Burkhart/AP Images for TV One hide caption

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