South carolina constitution
Article III: legislative department
Section 25

If any election district shall neglect to choose a member or members on the day of election, or if any person chosen a member of either house shall refuse to qualify and take his seat, or shall resign, die, depart the State, accept any disqualifying office or position, or become otherwise disqualified to hold his seat, a writ of election shall be issued by the President of the Senate or Speaker of the House of Representatives, as the case may be, for the purpose of filling the vacancy thereby occasioned for the remainder of the term for which the person so refusing to qualify, resigning, dying, departing the State, or becoming disqualified, was elected to serve, or the defaulting election district ought to have chosen a member or members.