Story highlights Among likely Democratic primary voters in South Carolina, Hillary Clinton has 69% support over Bernie Sanders' 21%

With black voters, Clinton's has a 77% lead over Sanders, who has 12% support

Washington (CNN) Hillary Clinton has maintained a nearly 50-point lead over Vermont senator Bernie Sanders and former Maryland Gov. Martin O'Malley in the early primary state of South Carolina, a new poll released Tuesday has found.

A new Monmouth University survey of likely Democratic primary voters in the state shows Hillary Clinton's overwhelming support among black voters.

Overall, the poll found Clinton's support in the Palmetto State to be 69%, a 48-point lead over Sanders with 21% support. Clinton has an even greater lead among black voters, with 77% support over Sanders' 12%. O'Malley has 1% of the statewide Democratic vote, 3% of white Democrats and 0% support among black Democrats in South Carolina.

The findings are similar to a poll released last week from Winthrop University , which found that likely primary voters were leaning toward Clinton with 71% of the vote. She had an even larger lead among African-American voters with 80% support in that poll.

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