South Carolina Senate Election Winner

Platform comparison

Market context

The 2026 South Carolina Senate race has been thrown into unprecedented turmoil following the death of Republican nominee Lindsey Graham on 11 July, just two days after he secured the primary with 56.8% of the vote [3][4]. This sudden vacancy explains the current 20% crowd-implied probability for the Democratic option, as the Republican party must now appoint a replacement candidate under state law, a process that introduces significant uncertainty regarding the new nominee’s viability and name recognition [4].

Historically, seats held by deceased incumbents or nominees shortly before an election have seen volatile shifts; the 20% price suggests traders are pricing in a high risk that the Republican replacement could struggle to match Graham’s established dominance in a deep-red state, though South Carolina’s partisan lean usually favours the GOP [4]. Comparable cases of late-term nominee changes often result in temporary dips for the incumbent party before a new candidate consolidates support, making this a high-variance event where the appointment timeline will dictate price movement.

Traders must monitor the South Carolina Republican Party’s announcement of the replacement nominee, as the speed and identity of this selection will be the primary catalyst for the contract’s resolution [4]. The general election is set for 3 November 2026, and any delay in appointing a candidate could force a run-off or alter the campaign calendar, directly impacting the USDC liquidity on Polygon [3][4]. Recent coverage highlights the immediate procedural scramble following Graham’s death, which remains the critical dependency for assessing whether the 20% YES probability is an overreaction or a rational assessment of the new field [4].

Sources: 1 · 2 · 3 · 4 · 5

Methodology

Methodologically we separate two layers: the live probability (Polymarket mid-price) and the platform attributes (fee, KYC, settlement currency, payment rails). That keeps the comparison honest — a single canonical probability across the row, with the venue-by-venue trade-offs spelt out in the columns next to it.

Resolution & payout

Polymarket-based markets settle through the UMA Optimistic Oracle on Polygon. A proposer submits the outcome, a two-hour challenge window opens, and unchallenged proposals finalise the resolution. Payouts settle automatically in USDC the moment the result is final — no bookmaker, no delay.

Kalshi-based markets settle in USD via the CFTC-regulated clearinghouse. Betfair Exchange settles in GBP/EUR net of commission. Manifold is play-money and does not pay out real funds.

FAQ

Is this market available outside the US?

Polymarket itself is geo-blocked in the US/UK/EU. Always check the legal status of prediction markets in your jurisdiction before trading.

What's the difference between YES and NO shares?

A YES share pays $1.00 if the event happens, $0 otherwise. A NO share pays $1.00 if the event doesn't happen. The market price between 0¢ and 100¢ is the implied probability.

What does Polymarket cost to trade?

Polymarket itself charges 0% — the only cost is the Polygon network fee, typically under $0.01 per transaction. Off-chain venues like Kalshi or Betfair charge 2-7% commission.

Do I need to KYC for this market?

On Polymarket directly, no — it's wallet-based. Intermediary brokers like PolyGram trigger KYC only above $1,500 of lifetime trading volume; under that you trade pseudonymously with a single wallet address.

How reliable are the quoted odds?

The YES/NO percentages are the live mid-prices of the Polymarket order book. On deep markets they move every few seconds; on thinner ones you'll see short plateaus.