Former vice president Joe Biden won the South Carolina primary on Saturday, reviving his flagging campaign for the Democratic presidential nomination.

All of the major television networks projected the 77-year-old Biden as the winner just minutes after polls closed in South Carolina at 7:00 pm (0000 GMT).

The networks did not provide any vote totals but the early projections were an indication that Biden had scored a decisive win in the state where he was counting on heavy support among African-American voters.

Democratic presidential candidate Joe Biden won the South Carolina primary, reviving his White House hopes
Democratic presidential candidate Joe Biden won the South Carolina primary, reviving his White House hopes GETTY IMAGES / Sean Rayford

A South Carolina victory was seen as crucial to Biden's hopes of challenging Bernie Sanders, the 78-year-old senator from Vermont, for the Democratic nomination and the spot on the ticket in November against Republican Donald Trump.

Sanders has been the clear frontrunner in the race having won both New Hampshire and Nevada after finishing in a virtual tie in Iowa with former South Bend, Indiana, mayor Pete Buttigieg.

Biden finished fourth in Iowa, fifth in New Hampshire and second in Nevada and he desperately needed a win in South Carolina ahead of next week's "Super Tuesday," when 14 states go to the polls.

One-third of the delegates who formally choose the Democratic nominee at the July party convention will be up for grabs on Super Tuesday.

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