When Is The South Carolina Senate Runoff? Date, Matchup And Kalshi Odds
When is the South Carolina Senate runoff? Tuesday, August 25, 2026, two weeks after the August 11 special Republican primary ended with nobody clearing the majority bar. But the date is only half the answer. A runoff wipes a crowded board down to two names and restarts the race, and prediction markets don't wait for the second vote to tell you how that reset is expected to go: Kalshi has been trading the two-way matchup since primary night. The price already contains a judgment about where the eliminated candidates' voters land, and by the end of this page you'll be able to read that judgment straight off the board.
The Quick Answer
The South Carolina Senate special Republican primary runoff is Tuesday, August 25, 2026, between appointed Sen. Darline Graham Nordone and U.S. Rep. Ralph Norman. Kalshi prices Graham Nordone at 72 cents (an implied 72% chance) and Norman at 27 cents to win the nomination as of August 12, 2026. Why the race went to a second vote, how a two-candidate market prices a runoff, and who can actually cast a ballot on the 25th are all below.
Why August 25? South Carolina's Majority Rule
South Carolina primaries are not won by simply finishing first. Under the state's majority-vote rule, a candidate needs more than 50% of the vote to take the nomination outright; otherwise the top two finishers meet again two weeks later. The South Carolina Election Commission's special election schedule set that contingency date before a single vote was cast: primary on Tuesday, August 11, statewide runoff (if necessary) on Tuesday, August 25.
Necessary it was. The August 11 field, the special primary to fill the late Sen. Lindsey Graham's seat, drew roughly a dozen Republicans, and no one came close to the majority line; over 40% of the first-round vote went to candidates who are now off the ballot entirely. Interest ran well beyond a sleepy special, too. The Election Commission reported more than 61,000 early votes banked before primary day even arrived. A field that fragmented made a second vote the expected outcome all along, which is why the two-week sequel was already the live question on Kalshi before the first-round board had even settled.
Who's In The Runoff: Graham Nordone Vs. Norman
That fragmented field produced the two names on the August 25 ballot. Darline Graham Nordone led the first round. She is the appointed incumbent, sworn in this July to fill the seat of her late brother, Lindsey Graham, and the first woman ever to represent South Carolina in the U.S. Senate. She had never held elected office before the appointment, which makes the runoff her first real test in front of voters.
Ralph Norman, the U.S. congressman, finished second and edged out fellow Rep. Russell Fry for the final runoff slot; the Associated Press projected the top two after Fry battled Norman narrowly for the second spot through most of the evening. Fry, former Gov. Mark Sanford and the rest of the field are out, and that word "out" matters for the market mechanics below: on Kalshi, elimination isn't just a news event, it's a settlement event.
What The Kalshi Market Says Now
Here is the live two-way board, as of August 12, 2026:
| Market | Contract | Kalshi Price (Yes) | Implied Chance (Bid–Ask) |
|---|---|---|---|
| SC Senate Special Primary Winner (Runoff Aug. 25) | Darline Graham Nordone | 72¢ | 72%–74% |
| SC Senate Special Primary Winner (Runoff Aug. 25) | Ralph Norman | 27¢ | 27%–28% |
| SC Senate Winner, November General | Republican party | 88¢ | 87%–88% |
| SC Senate Winner, November General | Annie Andrews (D) | 11¢ | 11%–12% |
The row worth staring at is Norman's 27 cents. He finished second, not a distant also-ran, and over 40% of primary voters backed somebody who is no longer on the ballot; on paper, that is a lot of available vote. Pricing him at 27% is the market saying it doesn't expect him to consolidate enough of it: traders are betting the appointed incumbent's first-round lead holds through the two-week sprint, and the 45-point gap between the two prices is the size of that conviction. This is the judgment we promised you could read off the board. The price isn't a poll of who's ahead today; it's a forecast of where the orphaned votes go on the 25th.
For the deeper candidate-by-candidate modeling behind this race, our South Carolina Senate special election odds page tracks the runoff market in full, and the 2026 midterm election odds hub carries every board this cycle. If you're newer to reading these boards, our look at whether prediction markets are actually accurate is the right primer.
How Runoff Pricing Works On Kalshi
A runoff does something clean to a prediction market: it turns a messy multi-candidate event into a two-contract board. Each remaining candidate has a Yes contract that pays $1 if they win the nomination and $0 if they don't, so the price in cents reads as the market's implied probability. Unlike a sportsbook line, there's no house setting the number; traders set it against each other, a distinction we unpack in prediction market vs. sportsbook.
A Worked Example At Today's Prices
Buy Norman Yes at his 27-cent last-traded price and you're risking $0.27 to collect $1.00 if he wins the nomination, roughly 3.7 times your money, a return that only makes sense if you think his true chance is better than 27%. Buy Graham Nordone at her 72-cent last price and you're laying $0.72 to win $1.00, a bet that her true chance is better than 72%. One practitioner detail before you take those numbers literally: a market order actually fills at the ask, which was 28¢ for Norman and 74¢ for Graham Nordone at this writing, so the "one number" you see is really a narrow window and your true breakeven sits a point or two above the last price unless a resting bid fills. The two active prices sit within a few cents of a dollar combined, which is exactly what a coherent two-way market should look like.
Everyone else's contracts are already gone. When Fry was eliminated on primary night, his market, like Sanford's, Nancy Mace's and the rest, settled No at $0 without waiting for August 25. That's the callback to "out" from earlier: a runoff market only ever carries the two survivors, and Kalshi typically settles once the result is called — the eliminated contracts settled within hours on primary night. Until then, the prices move on endorsements, runoff polling and turnout signals, the same way any live election board does.
Can You Vote In The Runoff?
The runoff has a crossover rule that catches people every cycle. Per the Election Commission's voter reminders, voters who participated in the June Democratic primary are not eligible in this Republican special contest; those who voted in the June Republican primary, or who sat out both June primaries, are eligible. Bring a photo ID — a South Carolina driver's license, DMV ID card, photo voter registration card, military ID or passport all qualify — and expect the polls to run 7 a.m. to 7 p.m., as they did on primary day. The rule also feeds the market read from earlier: the eligible runoff electorate is capped at people who could vote in the Republican special in the first place, so when traders price where the orphaned 40%-plus goes, they're pricing turnout inside that fixed pool, not new voters discovering the race.
What Happens After August 25
The runoff winner becomes the Republican nominee and faces Democrat Annie Andrews, a pediatrician, in November's general election. The market has already skipped ahead to that question too: Kalshi's November board prices the Republican side at 88% to Andrews' 11%, which is the quiet reason the runoff is where the real action is. Look closely at how that November board is built: Andrews is listed by name, but the Republican side trades only as "Republican party," because Kalshi can't post a named contract for a nominee who doesn't exist yet. Until the runoff settles, the 72–27 board is the only place to trade the "which Republican" question — and since the market treats the nomination as most of the ballgame in this seat, it's effectively pricing who South Carolina's next senator will be.
That's the whole story of this race in one line: a majority rule forced a reset, the reset produced a two-name market, and the market says the appointed incumbent is expected to finish the job her first-round lead started. If following live election boards is your thing, the same read-the-price approach works across every race this cycle — start with our guide to when polls close and how markets react, and if you want the sharp side of the site while you're here, the free expert picks page is the no-cost way in. This page stays on this URL and gets rebuilt whenever the next runoff rolls around; check back on the morning of August 26 for the settled board.
FAQ
When is the South Carolina Senate runoff? Tuesday, August 25, 2026. Polls are expected to run 7 a.m. to 7 p.m. as on primary day, and the date comes straight from the South Carolina Election Commission's special election calendar.
Who is in the runoff? Appointed Sen. Darline Graham Nordone, who led the first round, and U.S. Rep. Ralph Norman, who edged Rep. Russell Fry for the second spot on August 11.
What do the markets say? Kalshi prices Graham Nordone at 72¢ and Norman at 27¢ to win the nomination as of August 12, 2026. Prices move around the clock, so treat these as a snapshot, not a settled result.
When does the market settle? Kalshi typically settles once the result is called; the eliminated candidates' contracts settled No at $0 within hours on primary night. Only the two survivors still trade.
