August 26, 2026
President Donald Trump has regained some of the political momentum that appeared to be slipping away after a series of defeats by his endorsed candidates in Republican primaries. Two important runoff victories Tuesday — in South Carolina and Oklahoma — offered Trump a much-needed demonstration that his influence over the Republican base remains significant, particularly when he is prepared to personally campaign for his preferred candidates.
South Carolina victory becomes the biggest test of Trump’s influence
The most closely watched contest was the Republican Senate runoff in South Carolina, where Sen. Darline Graham defeated Rep. Ralph Norman and secured the Republican nomination for the seat formerly held by her late brother, Sen. Lindsey Graham.
Darline Graham won roughly 52 percent of the vote, compared with about 48 percent for Norman. Her victory was significant because she entered the runoff facing serious questions about her political experience and ability to compete against a more established Republican lawmaker.
Trump had endorsed Graham and went much further than simply issuing a statement of support. He traveled to Myrtle Beach on Aug. 21, held a rally and urged Republican voters to treat the contest almost as if Trump himself were on the ballot.
That personal intervention appears to have mattered. The Washington Post reported that Trump's political operation, including the pro-Trump super PAC MAGA Inc., spent more than $825,000 on get-out-the-vote efforts for Graham during the final weekend. Graham and her allies also dramatically outspent Norman on television advertising during the short runoff campaign.
The result therefore provides an important distinction about Trump's endorsement power: a Trump endorsement by itself may not guarantee victory, but an endorsement combined with personal campaigning, money and direct appeals to Republican voters can still be highly effective.
Trump's recent losing streak had raised questions
The South Carolina result was particularly important because it came after a difficult stretch for Trump's endorsed candidates.
Several Trump-backed Republicans have recently lost primary contests, including candidates in gubernatorial races in Iowa, Georgia, Minnesota and Wyoming. His endorsed congressional candidates also suffered defeats, including Reps. Andy Ogles in Tennessee and Cory Mills in Florida.
Those losses created an unusual problem for a president who has built much of his Republican influence around the idea that his endorsement can determine primary outcomes.
Trump's political brand has long been closely connected to his ability to mobilize Republican voters against candidates he considers insufficiently loyal to his agenda. A continued string of defeats could have encouraged Republican candidates and voters to become less dependent on his support.
Tuesday's results interrupted that narrative.
Trump did not simply rely on his endorsement
The South Carolina campaign also demonstrated that Trump recognized the race as a potential threat to his political standing.
Graham had already received Trump's endorsement before the Aug. 11 primary, but she received only about one-third of the vote in a crowded 10-candidate field. That forced her into a runoff against Norman.
Instead of assuming that his endorsement would be sufficient, Trump personally intervened.
His decision to travel to South Carolina was unusual for a president involved in a state-level primary. At the Myrtle Beach rally, he directly asked voters to turn out for Graham and portrayed the contest as partly a test of their support for him.
The strategy paid off.
The Washington Post noted that Horry County, where Trump held his rally, produced particularly strong support for Graham.
That suggests Trump's strongest influence may still come from highly engaged Republican voters who respond to his personal appeals rather than simply to his name appearing on an endorsement list.
Graham's lack of experience remained a major issue
Graham's victory was not without controversy.
Unlike her brother Lindsey Graham, who spent decades in national politics and became deeply involved in foreign policy and national security, Darline Graham had never previously held elected office before being appointed to serve the remainder of her brother's Senate term.
During the campaign, she faced criticism after acknowledging that she was not particularly knowledgeable about national security during a debate. She also faced questions about her positions on abortion policy and immigration.
Her opponents attempted to use those moments to argue that she was not prepared to serve in the Senate.
Trump took the opposite approach. Rather than treating her lack of experience as a weakness, he portrayed her as someone focused on everyday economic concerns and argued that she could surround herself with experienced advisers on foreign policy.
Graham herself embraced the outsider image, effectively arguing that being a conventional politician was not necessary to represent Trump's political movement.
Oklahoma provides a second boost
Trump's influence was also tested in Oklahoma, where his endorsed candidate Mike Mazzei narrowly defeated Attorney General Gentner Drummond in the Republican gubernatorial runoff.
The race was highly competitive. Drummond had actually led the June primary by less than one percentage point, while Mazzei finished second. Trump had endorsed Mazzei, but the endorsement alone did not produce an overwhelming first-round victory.
During the runoff, Trump continued to campaign against Drummond and portrayed him as insufficiently aligned with the administration's agenda.
Mazzei ultimately prevailed by a razor-thin margin.
The Oklahoma result reinforces a broader point from Tuesday's elections: Trump's influence remains powerful, but Republican voters are not automatically following his preferences in every contest.
What the results mean for the 2026 midterms
The victories could have consequences beyond the two individual races.
Republican candidates preparing for the 2026 midterm elections will be watching closely to determine whether Trump's endorsement remains an essential asset. A candidate who can secure Trump's backing may gain access to his political network, fundraising infrastructure and highly motivated supporters.
At the same time, recent primary defeats show that Republican voters retain the ability to reject candidates backed by the president.
The South Carolina contest may therefore represent a more useful measure of Trump's political strength than a simple endorsement victory. Trump recognized that Graham was vulnerable, personally entered the race and mobilized his political operation behind her.
That effort produced a win.
A victory, but not an unlimited mandate
The results should not necessarily be interpreted as proof that Trump's influence has returned to its previous peak.
Graham's victory was relatively narrow, and Mazzei's Oklahoma win was even closer. In both cases, Trump's involvement was substantial. That makes it difficult to conclude that his endorsement alone was responsible for the outcomes.
Instead, Tuesday's results demonstrate that Trump can still activate Republican voters when he makes a race a personal priority.
The distinction could become increasingly important as the 2026 midterm elections approach.
For Trump, the immediate takeaway is positive: after months in which his endorsed candidates repeatedly stumbled, his preferred candidates won two consequential Republican runoffs on the same night.
For Republicans, however, the lesson is more complicated. Trump's endorsement remains powerful, but candidates may still need strong organizations, substantial spending and a message that resonates with voters.
And for the broader Republican Party, the results offer another indication that Trump's influence remains central to the party — even if it is no longer completely unquestioned.
Also Read: Oklahoma Runoff Tests Trump’s Grip on GOP Voters