S.C. Code § 7-13-370
If any candidate dies, withdraws or otherwise becomes disqualified after his name has been printed on an official election ballot and if any person is nominated, as authorized by law, to fill such vacancy, the name of the candidate so nominated to fill such vacancy need not be printed upon the ballots, but the name of such candidate so nominated shall be certified by the party executive committee making the nomination to the officer, commissioners or other authority charged with the duty of printing such ballots and a vote cast by a voter for the name of the candidate printed on the ballot who has either died, withdrawn or otherwise become disqualified shall be counted as a vote for the candidate subsequently nominated to fill such vacancy whose name is on file with such officer, board of voter registration and elections, or other authority.
S.C. Code § 7-13-370