President Donald Trump said he would “soon” endorse a candidate in the Republican primary runoff for U.S. Senate and, in doing so, call on whomever he does not endorse to drop out of the race — though he did not specify whether he would back Sen. John Cornyn or Attorney General Ken Paxton.

In a post on Truth Social, Trump said that the stakes of Texas’ Senate race in November are too high to allow the Cornyn-Paxton contest to go on. The two Republicans finished just over one point apart in Tuesday’s primary, but neither reached the majority threshold to win outright, forcing a May 26 overtime round.

“The Republican primary race for the United States Senate in the Great State of Texas, a State I LOVE and won 3 times in Records Numbers (the HIGHEST vote ever recorded, by far!!!), cannot, for the good of the Party, and our Country, itself, be allowed to go on any longer,” Trump wrote. “IT MUST STOP NOW!”

Touting the power of his endorsement in Texas — nearly all of the candidates he backed won outright or advanced to runoffs — Trump said he planned to weigh in imminently.

“I will be making my Endorsement soon, and will be asking the candidate that I don’t Endorse to immediately DROP OUT OF THE RACE!“ Trump said. “Is that fair? We must win in November!!!”

With nearly all the vote tallied in Tuesday’s primary, Cornyn led with 42% to Paxton’s 41%, according to unofficial returns.

Trump said the eventual nominee must run a better race.

“Both John and Ken ran great races, but not good enough,” he wrote. “Now, this one, must be PERFECT!”

The White House has stayed out of the bruising primary race between Cornyn and Paxton, which has already seen nearly $100 million in spending and divided the Texas GOP. Both camps have made overtures to Trump for his endorsement, convinced it will be the decisive factor in the race.

At a rally in Corpus Christi Friday before the primary, Trump intimated that he had “pretty much” decided who to back while declining to name his pick.

The contest to earn Trump’s endorsement has been nearly as furious as the primary itself, intensified by Trump’s clear interest in the race but decision to stay out thus far.

Cornyn and his allies, including Senate Majority Leader John Thune, have made a financial and electability-backed argument to Trump, saying that Paxton would be laden down by his history of legal and personal baggage if he is the nominee, costing Republicans untold millions in the general election that could be spent in more competitive states. Cornyn has also contended that Paxton’s candidacy would imperil down-ballot Republicans, particularly in U.S. House races.

Paxton, by contrast, has argued that his grassroots support among the MAGA base of the party will make it easier for Republicans to turn out the lower-propensity members of Trump’s coalition who tend to stay home when the president is not on the ballot and counteract Democratic enthusiasm.

Republicans in Washington and Texas, including Cornyn, have been clear-eyed about the danger they see in the Democratic nominee, state Rep. James Talarico. They openly rooted for his primary opponent, U.S. Rep. Jasmine Crockett, and while they believe Talarico is flawed, some Republicans acknowledge it could be a more expensive proposition to negatively define the state legislator, who was less well-known than Crockett.

Without acknowledging Talarico by name, Trump labeled him the “Radical Left Opponent” and said the party must “TOTALLY FOCUS on putting him away, quickly and decisively!”

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