S.C. Code Ann. § 7-13-2210: General or special election.

If any general election or special election, other than a nonpartisan municipal election, results in a tie vote and no candidate withdraws, the election officials who conducted the tie election shall conduct a runoff election to break the tie two weeks following the tie election. In the tie-breaking runoff, the laws of this State apply, mutatis mutandi. If the date for the tie-breaking runoff falls on a legal holiday, it must be held on the same day of the first week following which is not a legal holiday.