Will Lindsey Graham face a runoff because of his Iran war support?

One by one, the Republican candidates walk to the front of a cavernous church to address a mostly elderly group of voters gathered on a midweek evening in this solidly conservative corner of South Carolina.

Sen. Lindsey Graham, the four-term GOP incumbent they’re hoping to unseat, is not among them. A longtime fixture of South Carolina politics and a golfing buddy of President Donald Trump, Mr. Graham has not faced a serious primary threat in years.

Lately, however, there have been faint flashes of discontent. Senator Graham has been one of the most dogged and high-profile advocates for the U.S.-Israel war against Iran – which polls show has grown increasingly unpopular, even among Republicans.

Why We Wrote This

Lindsey Graham is a powerful Senate incumbent. But the South Carolina Republican's promotion of the Iran war appears to be taking a toll with voters, raising doubts about whether he’ll surpass the 50% needed to avoid a runoff in Tuesday’s GOP primary.

A poll conducted late last month by The Citadel raised some eyebrows when it showed Mr. Graham falling short of the 50% needed in the June 9 primary vote to avoid a runoff.

To be clear, Mr. Graham is on track to win reelection, probably handily. As chair of the powerful Senate Budget Committee, with close ties to the president as well as powerbrokers in South Carolina, he can point to a long track record of delivering for his state. Though he gets lower approval ratings than other major Republican officeholders here, his incumbency is a powerful and self-reinforcing factor.

Beverly Hice, a retired business owner who went to see the other GOP candidates at the forum in Fort Mill, says she’s “not really fond” of Mr. Graham, but admits she’s likely to wind up voting for him anyway. He’s “a shoo-in,” Ms. Hice says.

Alex Brandon/AP

Sen. Lindsey Graham, center, talks with reporters alongside President Donald Trump and Commerce Secretary Howard Lutnick, aboard Air Force One, Jan. 4, 2026. A day earlier, the U.S. military had conducted an operation in Venezuela which led to the arrest of that country's president, Nicolás Maduro.

Mr. Graham’s political longevity is in many ways testament to his adaptive brand of conservatism. Once seen as a problem-solver who worked with Democrats on immigration reform during the Obama administration, he has pivoted during the Trump era toward a more pugnacious populism – and was rewarded with a place in Mr. Trump’s inner circle. He even finessed the fallout from Mr. Trump’s feud with Sen. John McCain of Arizona, who was considered a maverick among Republicans and had been Mr. Graham’s mentor and friend in the Senate before his death in 2018.

“He knows which way the political wind blows,” says Scott Huffmon, a political scientist who runs the Center for Public Opinion and Policy Research at Winthrop University in Rock Hill, South Carolina. “People say, ‘Oh we need to get Lindsey Graham out.’ But he always ends up in the right place at the right time.”

On the Iran war, though, Mr. Graham early on staked out a prominent and uncompromising position, making the case on television and on social media, and doubling down even as the military mission appeared to stall. Indeed, he is more closely identified with the conflict than perhaps any other lawmaker in Washington, having boasted about his role in convincing Mr. Trump to go to war.

As a result, any dip in Mr. Graham’s own political support might be an indicator of how voters are feeling about the war – and the resulting run-up in the price of gas and other staples – in a deep-red state where two-thirds of adults say groceries are difficult to afford.

Mark Lynch stages a challenge

Of the five Republicans running against Mr. Graham, four are polling in the single digits. Another candidate, attorney and Project 2025 architect Paul Dans, dropped out of the race in April after failing to gain much traction. The closest remaining challenger, Mark Lynch, was 10 percentage points behind Mr. Graham (46% to 36%) in the Citadel poll, and even further behind in a May poll by the Trafalgar Group (52% to 28%). If no candidate receives more than half of votes cast, the primary will proceed to a runoff.

Mr. Lynch, who owns an appliance store in Greenville, is financing his campaign with $5 million from his and his wife’s retirement fund. He says Mr. Graham’s voting record shows he isn’t a true conservative – that as Budget Committee chair, Mr. Graham failed to rein in deficit spending while advocating for raising the eligibility age for Social Security benefits. (Mr. Graham’s campaign has highlighted his role in passing Mr. Trump’s “One Big Beautiful Bill,” which eliminated taxes on Social Security for most seniors.)

But Mr. Lynch’s sharpest attacks are aimed at Mr. Graham’s hawkish foreign policy positions and his support for Israel. Conservatives in South Carolina generally supported Mr. Trump’s decision to strike Iran in order to prevent it from developing a nuclear weapon, but many are…