COLUMBIA, South Carolina (Reuters) - Democrats Barack Obama and Hillary Clinton looked on Sunday toward the next battles in a bruising White House race after Obama rolled to a huge win in a bitterly contested South Carolina primary.

Obama, an Illinois senator who would be the first black U.S. president, crushed Clinton in the latest showdown in a back-and-forth fight for the right to represent the Democratic Party in November's presidential election.

With heavy support from black voters, Obama doubled Clinton's tally to win 55 percent to 27 percent. John Edwards finished third with 18 percent in a state he won during his failed 2004 race, casting fresh doubt on the future of his campaign.

The win for Obama after two consecutive losses to Clinton, in New Hampshire and Nevada, gave him new momentum heading into February 5 "Super Tuesday" Democratic contests in 22 states. Obama won the first contest in Iowa.

"Tonight, the cynics who believed that what began in the snows of Iowa was just an illusion were told a different story by the good people of South Carolina," Obama told a cheering crowd in Columbia, the state capital.

"In nine short days, nearly half the nation will have the chance to join us in saying that we are tired of business-as-usual in Washington, we are hungry for change, and we are ready to believe again," he said.

Obama left South Carolina immediately after his victory to fly to Georgia, a state that votes on February 5. Clinton, the New York senator who would be the first woman president, left before the votes were even tallied to fly to Tennessee, another February 5 state.

"Now the eyes of the country turn to Tennessee and the other states that will be voting on February 5," she said in Nashville. "Millions and millions of Americans will have the chance to have their voices heard and their votes counted."

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