Using some of his most candid language so far this election cycle, President Barack Obama late Sunday suggested a Donald Trump presidency would be an “unmitigated disaster.” And he advised Democratic donors to prepare for a tense Election Day.

Speaking at a Sunday night fundraiser with 65 attendees at an upscale Manhattan apartment — attendees donated from $25,000 to $250,000 to the Democratic Party — Obama said of the Republican presidential nominee: “This guy is not qualified to be president.”

What’s more, the president said Trump “shows no interest in even gaining the rudimentary knowledge required to make really hard decisions on a day-to-day basis.” He sees in the real estate mogul “no curiosity” nor a “desire to get up to speed.”

The fundraiser was among several Obama will do this week while in New York for his final U.N. General Assembly session. Last week, amid questions about whether he has campaigned enough for Hillary Clinton, the White House suggested raising big chunks of campaign cash is as helpful as rousing voters at rallies.

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Obama charged Trump with not running a presidential campaign but “an infomercial — it’s a reality show.” Alluding to some of the GOP standard-bearer’s most controversial remarks on racial issues, the president warned that his candidacy is “tapping into some of our worst impulses as a country — ones that divide us rather than bring us together.”

Using strong language in an attempt to motivate the big-money donors to contribute or raise even more, the president, who for months would not utter Trump’s name, employed pointed language about what his election would mean.

“When I ran against John McCain, we had deep differences, but I couldn’t say that he was not qualified to be president of the United States,” Obama said. “When I ran against Mitt Romney, I had profound differences with him, but I couldn’t say that electing Mitt Romney would be an unmitigated disaster.”

Obama’s candor continued when discussing what he perceives will be a tight outcome on Nov. 8, saying: “So this should not be a close election, but it will be.”

A Morning Consult poll released Sunday shows a close race among likely voters, with Clinton clinging to 42 percent to 40 percent lead over Trump, but that was within the survey’s 2-point margin of error. 

But rather than pinning that potential Clinton-Trump photo finish on the Democratic nominee’s “flaws” or campaign-trail miscues, the president said a close outcome is almost inevitable because “structurally, we’ve become a very polarized society.”

He added that for Republican-leaning voters who only watch Fox News or listen to conservative radio host Rush Limbaugh, “it’s very hard for you to think that you’re going to vote for somebody who you’ve been told is taking the country in the wrong direction.”

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Obama, as he increasingly does during these intimate fundraisers with Democratic donors, also slipped in a jab at Trump’s business tactics.

“Some of you may have business with him,” he said. “If you have, it doesn’t sound like it’s been a pleasant experience.”

A reporter allowed into the apartment for Obama’s remarks heard “scattered giggles,” according to a dispatch released by the White House.

Where Obama used the fundraiser to cast Clinton as far more qualified to be the next chief executive than her GOP foe, Trump’s campaign on Sunday continued to suggest that she is corrupt.

“Secretary Clinton, in 2014, the Clinton Foundation spent less than 6 percent of its budget on charitable grants,” Jason Miller, the Trump campaign’s senior communications adviser, said in a statement. “Why is it that your foundation spent more money on overhead than it did on direct charitable grants?”

Contact Bennett at johnbennett@cqrollcall.com. Follow him on Twitter @BennettJohnT.