President Obama tore into Donald Trump today, flatly declaring him “unfit” for the presidency and calling on Republican elected officials to withdraw their support for him. Here’s what he said:

“The Republican nominee is unfit to serve as president. I said so last week, and he keeps on proving it…the notion that he would attack a Gold Star family, the fact that he doesn’t appear to have basic knowledge around critical issues — in Europe, in the Middle East, in Asia — means that he’s woefully unprepared….
“What’s been interesting is the repeated denunciations of his statements by leading Republicans….If you are repeatedly having to say in very strong terms that what he has said is unacceptable, why are you still endorsing him?”

Obama added: “There has to come a point at which you say, ‘Enough.'” Crucially, he noted that Trump stood apart from previous GOP nominees, such as John McCain and Mitt Romney, noting that he didn’t question their “basic decency,” and adding that if either had won, he would have been able to say to Americans that “this is our president, and I know they’re going to abide by certain norms and rules and common sense.” He concluded: “But that’s not the situation here.”

A number of people on twitter immediately pointed out that, by calling on Republicans to disassociate themselves from Trump, he actually made it less likely that this will happen:

This joke, as it were, actually gets at a serious argument that has unfolded among Democrats. Should Dems want Republicans to cling to Trump, so the whole party and its down-ticket incumbents and candidates are tainted by Trumpism, and (for longer term purposes) so the GOP bears some responsibility for its role in creating the conditions for Trumpism’s rise, thus making a full GOP reckoning (and a saner opposition party) after a Trump loss more likely?

Or should Dems continue to press the case that Trumpism is an outlier relative to the GOP and conservatism, in order to make it easier for GOP-leaning swing voters to vote for the Democrats?

Obama’s remarks today, taken along with his speech at the Democratic convention, indicate that he has chosen the latter course. Both of those sets of comments — and particularly his convention speech — make the case that Trump represents a unique emergency, one that, in essence, is a threat not just to the country, but to the political order that the GOP, too, has a continued stake in preserving.

Obama may or may not believe that GOP lawmakers will actually break from Trump in substantial numbers. But his argument to them — like his convention speech — is also intended as a message to millions of Republican-leaning voters, such as suburban women, college educated whites, and GOP-leaning independents. That message is basically that Trump is a special case. Obama is appealing to those voters to appreciate just how uniquely unfit Trump really is — to take into account his hostility towards demographically diversifying America, his ignorance and lack of basic curiosity about the world, his swaggering authoritarianism, his obvious indifference to the constitutional order, and his ongoing, ever-worsening, seemingly sociopathic display of abusive tendencies — as they make their choice.

It’s possible that this argument — that Trump is temperamentally and morally unfit for the office in a way previous GOP nominees have not been — could resonate. The new CBS News poll finds:

Sixty one percent of American voters say Trump is not prepared for the job, and 63 percent say he lacks the right temperament for it. Meanwhile, equally large majorities say Clinton does possess those qualities.

Meanwhile, political scientist Lynn Vavreck has an interesting piece today arguing that Trump’s success may be inextricably linked to deeper ongoing changes underway inside the GOP. The short version of the argument is that Trump is benefiting from, and accelerating, the shift of white men without college degrees to the GOP, but he may also be accelerating the shift of white women overall and white men with college degrees to the Democrats. As Vavreck bluntly puts it, Trump may be “helping Hillary Clinton expand the Democratic Party,” even as he is “reshaping his own party by shrinking it.”

As I’ve reported, Democrats believe the nomination of Trump  may present a unique opportunity to realize this shrinkage. Now, all of this optimism may prove to be completely wrong; Trump could still win. Or Clinton could prevail in a very close contest, and the GOP could quickly right itself in 2018 or 2020. Talk of electoral re-alignment is almost always overstated or illusory.

But the fact remains that Trump is on track to become the first GOP nominee to lose among college educated whites since the early 1950s, and he looks poised to alienate women in historic numbers. Obama’s bet is that the best way to make that happen is to make this election a referendum not on a Trump-tainted GOP, but on Trump himself — specifically, on his impressive dual status as both uniquely unfit for the office and a singularly repellent figure.