Two of the Republican Party's most prominent strategists agreed Sunday that Donald Trump is tapping into a deep well of voters' dissatisfaction with Washington — but they both insisted he won't win the party's nomination for president.
"There's a lot of frustration and anger in the country about the federal government, and about politicians in both parties. And Donald has become a vehicle for that kind of frustration," said Charlie Black, a senior adviser to Sen. John McCain's 2008 presidential bid, on NBC's "Meet the Press."
Black said he does believe he's "here to stay for a while, maybe through a few primaries — but he is not going to be the nominee."
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Alex Castellanos, a former campaign adviser to both Jeb and George W. Bush, offered a similar evaluation of Trump's chances, saying he won't be able to grow his support past 40 percent, if that, and while the real-estate mogul "surprised us…I don't think he's going to be the nominee in that sense."
He pegged Trump's appeal as offering an attractive contrast to President Obama's governing style over the past seven years, which had been characterized by "soft power and dialogue and, you know, crossing red lines. Donald Trump is the reaction to that."
"When the world is spinning apart, you want somebody to grab the reins. The other guys are going to have to grow here," Castellanos added.
But the two both agreed that Trump's Achilles heel may be that his record doesn't always match his rhetoric — that Trump once identified as a Democrat, supported liberal policy priorities and praised Democratic lawmakers before running for president as a Republican.
"Wait until [Trump's supporters] learn that the guy's been a Democrat longer than a Republican, that he's advocated for things like partial birth abortion, universal healthcare run by the government," he said.
Trump's rise in the polls has flummoxed political strategists and pundits, most of whom initially predicted he would again sit the race out, and then later speculated Trump would do enough damage with his controversial rhetoric that he would be forced to drop out of the race.
Prognosticators were wrong on both counts, and Trump has enjoyed a lead in every national poll conducted since early July. That has many Republican elders worried about the impact Trump could have on the party's competitiveness, if he drags other candidates to the right or turns off minority or female voters with his rhetoric.
Black, echoing the sentiment expressed behind closed doors by many GOP leaders, offered a complement — and then a jab — for Trump.
"I am a friend and admirer of Donald Trump. But he's not suited to be president, and he will not be president," he said.
This article originally appeared on NBCNews.com