The first woman to graduate from The Citadel has won a Republican runoff for a South Carolina House seat vacated amid a Statehouse corruption investigation.

Daniel Island businesswoman Nancy Mace won nearly 63 percent of votes cast in Tuesday's voting, defeating former Mount Pleasant Town Councilman Mark Smith.

The District 99 seat was vacated when Jim Merrill resigned shortly before pleading guilty to misdemeanor misconduct in office. The district covers parts of Charleston and Berkeley counties.

Mace got 49 percent of the vote in a four-way primary, just shy of the majority she would have needed for an outright win.

Mace graduated from The Citadel in 1999 and was a field director for Donald Trump's campaign. She faces Democrat Cindy Boatwright in a special election Jan. 16.