Polls Suggest Wilson Leads in South Carolina Gubernatorial Runoff

Hours before South Carolina Republicans vote, a final poll shows Attorney General Alan Wilson leading in the gubernatorial runoff. An InsiderAdvantage survey, conducted among 800 likely Republican voters on June 19-20, indicates Wilson has 61% support. Lieutenant Governor Pamela Evette trails with 29%, and 10% remain undecided.

A late shift toward Wilson may determine the nomination as low turnout amplifies small changes. Both candidates received endorsements from President Donald Trump, making the race more about organization and turnout.

Key Points

• An InsiderAdvantage poll shows Wilson at 61%, Evette at 29%, with 10% undecided.
• Earlier polling indicated no clear leader in a fragmented field.
• Prediction markets now heavily favor Wilson, giving him more than 98% odds.
• South Carolina generally leans Republican, making the primary winner likely to succeed in November.

How the Primary Unfolded

The runoff follows a crowded June 9 primary where no candidate gained a majority. Evette received 28.9% of the vote, while Wilson got 26.1%. Representatives Nancy Mace and Ralph Norman, who did not advance, have backed Wilson, providing a boost. Outgoing Governor Henry McMaster, who supports Evette, is term-limited and unable to seek reelection.

Evette’s campaign highlights the choice between “a proven business leader and conservative fighter” and “a career politician supported by taxpayer dollars.” Her strategy focuses on voter outreach, emphasizing turnout’s role in the runoff and promoting a conservative vision for South Carolina.

What the InsiderAdvantage Poll Shows

The most recent poll, using mixed-mode text and panel methods, reflects a shift to Wilson. The poll included adjustments for age, race, and gender, with a 3.46% margin of error. Results show a dramatic 30-point margin indicating voter consolidation around Wilson after other candidates were eliminated. Even undecided voters favoring Evette may not overcome this lead.

What Polling Averages Show

Prior to the primary, polling averages showed a tight race with no dominant candidate:

• RealClearPolitics: Evette 20.2, Wilson 18.2
• Race to the White House: Evette 19.3, Wilson 17.6
• Decision Desk HQ: Evette 19.6, Wilson 18.5
• 270toWin: Wilson 18.8, Evette 18.7
• FiftyPlusOne: Evette 20.1, Wilson 17.4

The average showed Evette with 19.6% and Wilson 18.1%, illustrating fragmentation. The elimination of weaker candidates often consolidates votes, benefiting broader appeal rather than a strong initial base.

What Prediction Markets Say

Prediction markets now strongly predict a Wilson victory:

• Kalshi: Wilson 98.4%, Evette 1.5%
• Polymarket: Wilson around 98%

These platforms combine polling, news flow, campaign signals, and trader expectations. They can outperform traditional polls but have limitations, including liquidity and representation of the voting population.

What Forecasters Say About the General Election

Looking ahead, forecasters agree South Carolina is solidly Republican:

• Inside Elections: Solid Republican
• Race to the White House: Likely Republican
• RealClearPolitics: Likely Republican
• Sabato’s Crystal Ball: Safe Republican
• Cook Political Report: Solid Republican

The GOP primary winner is favored against the Democratic nominee, State Representative Jermaine Johnson, who won his primary with 59.7%.

What Happens Next

The data suggests the race may structurally favor Wilson, with runoffs typically showing low turnout. Unexpected outcomes could arise from mobilization efforts. Polls in South Carolina open from 7 a.m. to 7 p.m., and the decision may lie in voter turnout.