Richland County elections and voter registration director Rokey Suleman resigned after the Post and Courier of Charleston reported that nearly 1 percent of the 142,000 votes cast in November's election were not counted.
State election officials say they don't think the uncounted ballots would have changed the outcome of any races.
Richland elections board chairwoman Jane Emerson said the decision to quit Saturday was Suleman's. Emerson said she thinks he wanted to step down while officials figure out what happened.
Richland County elections have been plagued with problems. During the 2012 presidential election, many voters waited hours to vote.
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