President Donald Trump avoided a major political embarrassment on Tuesday night when Sen. Darline Graham, the Republican candidate he went all in for, defeated Rep. Ralph Norman in a U.S. Senate primary runoff in deep-red South Carolina. But conservative journalist Bill Kristol — a veteran of the Reagan and George H.W. Bush administrations who has become one of the right's most prominent Trump critics — argues in The Bulwark, which he co-founded, that Graham's victory was far from a landslide — she prevailed by roughly 4 percent, according to the Associated Press (New York Times election coverage).

Kristol contends that the "unhinged and erratic" president remains a "flailing president presiding over a failing administration."

"I regret to report that Donald Trump notched a couple of wins last night," Kristol writes in the conservative outlet. "He helped pull Sen. Darline Graham across the finish line in the runoff for the Republican Senate nomination in South Carolina, as she defeated Rep. Ralph Norman 52 to 48 percent. And the candidate Trump endorsed in the GOP runoff for governor of Oklahoma, Mike Mazzei, edged out state Attorney General Gentner Drummond for that nomination by half a point. The good news is that both were close calls. The Trump-backed candidates came close to losing."

Kristol points out that Norman and Drummond "are Republicans who were opposed by Trump" but "almost won."

"Put last night's results together with Trump's continued erosion in national polls, and one can say that the president is weaker than he perhaps has ever been politically — not just in terms of support among the general public, but even in his own party," Kristol explains. "Make no mistake: He still dominates and controls it. But in a new Reuters-Ipsos poll, which has only 33 percent of Americans overall approving of Trump's job performance against 65 percent disapproving, one can see slippage even among Republicans: 18 percent of Republicans disapprove of Trump's job performance, and of the 82 percent who approve, only 35 percent strongly approve while 47 percent only somewhat approve" (Reuters/Ipsos topline).

Primary results inside a president's own party are routinely watched as an early gauge of his clout with his base — a measure that takes on added significance with the November midterm elections, in which all 435 House seats and roughly a third of the Senate are on the ballot, now only weeks away.

Kristol warns, however, that Trump's "flailing" does not make him any less "dangerous."

"So, the public, including some Republicans, is moving away from Trump," Kristol writes. "His key policies, such as the Iran war and the tariffs, are clearly failing…."

"But he remains a very dangerous president — more dangerous than ever, I'd say. Desperate men do desperate things. And desperate groups of men do desperate things. So a desperate Trump is becoming more megalomaniacal than ever. And the Trump administration is becoming ever more radical in pursuing its authoritarian projects."