Graham's SC Senate seat stays Republican, decided in the Aug 25 GOP runoff by Trump's endorsement

STRUCTURAL / THESIS CALL. Lindsey Graham (R-SC) died July 11, 2026 as the certified June-9 Republican nominee. Under SC Code 7-11-55 the replacement nominee was chosen by a special GOP primary of the voters (Aug 11, runoff Aug 25) — and the outcome is now known: his sister DARLINE GRAHAM, appointed to the seat by Gov. McMaster July 13, led the 10-candidate primary at 33% and WON the Aug 25 runoff over Rep. Ralph Norman, 52.5% to 47.6%, with Trump's endorsement and a Myrtle Beach rally — exactly the endorsement-decides-the-sprint path this call priced. She faces Democrat Annie Andrews, a Charleston pediatrician, on Nov 3. South Carolina has not elected a Democratic senator since 1998, so the seat stays Republican in the base case — but the late-September Trafalgar poll had Graham only +1 over Andrews (43-42), which is the watch: if tight polling holds to the vote, this level comes down. EHIQ 87%; the dated venue leg prints beside this card.

• •Mechanism: Graham was the certified June-9 nominee, so SC Code 7-11-55 triggered a special GOP primary of the voters (Aug 11, runoff Aug 25); the November general date did not move.
• •Nominee decided: Sen. Darline Graham (appointed by Gov. McMaster in July) won the Aug 25 runoff over Rep. Ralph Norman with about 52.5% of roughly 369,000 votes, with Trump's endorsement.
• •General: Graham faces Democrat Annie Andrews, a Charleston pediatrician, on Nov 3. South Carolina has not elected a Democratic senator since 1998.
• •The watch: the late-September Trafalgar poll had Graham 43, Andrews 42 (+1); an August Impact Research poll had Andrews +3. If tight polling holds to the vote, this level comes down.
• •Control unaffected: Senate 53R-47D, Democrats need +4; SC is not a top-tier battleground.

Resolution source: Polymarket settlement of `will-the-republicans-win-the-south-carolina-senate-race-in-2026`. That market resolves on the WINNER'S PARTY in the 2026 South Carolina U.S. Senate election, inclusive of any run-offs, treating a candidate as representing a party when they are that party's nominee. This call asks whether A REPUBLICAN wins the seat, which is the same proposition the market pays on, so the venue settles it directly. Verified against the venue's published description 2026-09-01.

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