The South Carolina GOP primary to fill the Senate seat left vacant by the late Sen. Lindsey Graham is projected to proceed to a runoff election on Tuesday, August 25, 2026, according to Decision Desk HQ. The runoff will feature Sen. Darline Graham and Rep. Ralph Norman competing for the Republican nomination.

Lindsey Graham, 71, died unexpectedly in early July 2026 after serving in the Senate for more than two decades. Following his passing, South Carolina Governor Henry McMaster appointed Darline Graham, the late senator's sister, as an interim replacement. She is now running for a full term in the traditionally red state.

With a crowded field in the fast-tracked special election, no candidate secured a majority vote to avoid a runoff. An Emerson College Polling survey from late July showed Darline Graham trailing Norman, with 19 percent and 22 percent support respectively, both well below the majority needed to win outright. Other candidates in the race include former Gov. Mark Sanford and businessman Mark Lynch.

Darline Graham's campaign is bolstered by support from former President Donald Trump, who recommended her as an interim replacement and later urged her to run for a full term. Trump stated, “I hope Darline does this, in that there would be nobody better to honor the legacy of her beloved brother, Lindsey,” noting his strong electoral history in South Carolina.

The runoff election will determine who will appear on the November ballot to succeed the late Sen. Lindsey Graham.

Sources

The Hill: Graham, Norman advance to runoff in South Carolina GOP primary for Senate