S.C. Code Ann. § 57-21-80

On closing the polls the managers shall count the ballots and shall make returns of the results of the election with the original ballots cast and the tally sheets to the governing body of the county who shall declare the results of the election. The validity of the election and correctness of the determination of the results thereof by the governing body of the county shall not be open to question in any court except in a suit or proceeding commenced within thirty days after the date of the election.