Crowded field forms in South Carolina's special U.S. Senate Republican primary

The Wire: The race to replace the late Sen. Lindsey Graham on South Carolina's November ballot is filling fast, with former Gov. Mark Sanford jumping in Thursday and filing set to close July 28 ahead of an Aug. 11 special Republican primary.

Why it counts: President Trump has already made his pick, endorsing appointed Sen. Darline Graham Nordone, and the field has kept growing anyway. In a state Trump carried by 18 points in 2024, the primary doubles as a test of whether his endorsement still clears a Republican field.

The margin: Early polling shows no clear leader. An Emerson College/Nexstar survey of 500 likely GOP primary voters taken July 14-15 found Graham Nordone at 5.9%, with a large share of the electorate undecided and a 4.3-point margin of error.

The fine print: The calendar is brutally short. Filing opened at noon July 21 and closes at noon July 28, the same day as Lindsey Graham's funeral in Washington. If no candidate clears 50% on Aug. 11, which is likely in a field this size, the top two meet in an Aug. 25 runoff.

On the record: Graham Nordone, who has never held elected office, is running on her state service record. "I've worked for almost 30 years for the people of this state," she said.

The counter: Trump's endorsement has not budged his rivals. Rep. Ralph Norman, who asked for the president's backing and was told it was too early, said flatly that he would stay in the race: "We've got a country to save." Rep. Russell Fry, whom Trump had earlier called an outstanding option for the seat, entered July 20 pitching generational change. Norman also picked up an endorsement from retiring Rep. Nancy Mace, who declined to run herself.

The backdrop: Senate Republicans are split. Majority Whip John Barrasso is backing Graham Nordone, while Majority Leader John Thune is staying neutral, calling her a strong candidate while noting she lacks elected experience. The field also includes businessman Mark Lynch, who lost to Lindsey Graham by nearly 28 points in last month's primary. Norman finished third in June's gubernatorial primary behind Lt. Gov. Pamela Evette and Attorney General Alan Wilson, a race that already tested Trump's sway in the state.

Looking ahead: More candidates could still file before Tuesday's deadline. The winner of the Aug. 11 primary, or the Aug. 25 runoff if one is needed, faces Democratic nominee Annie Andrews, a Charleston pediatrician, on Nov. 3.