The crisis swirling around Donald Trump’s presidential campaign is unique, but there’s nothing unprecedented about congressional candidates distancing themselves from a locally unpopular presidential candidate.

Back in the 2012 cycle, for example, we had a smattering of Democrats from red states who declined to endorse Barack Obama’s reelection. At the time, the reaction within the Obama White House was to treat that as all in the game. Democrats would rather Joe Manchin represent West Virginia than a Republican, so if Manchin needs to criticize Obama now and again to stay viable, that’s politics. It’s nothing personal.

Trump’s attitude toward Republicans throwing him under the bus has been very different. In talking points circulated to campaign surrogates Sunday morning and reported by Jonathan Martin of the New York Times, Trump’s campaign is instructing its allies to punch back at Trump’s intra-party critics.

“A lot of the people who are being so critical now are the same ones who doubted him before,” read the talking points, which were forwarded by a Republican strategist. “They are more concerned with their political future than they are about the future of the country. Mr. Trump won the Primary without the help of the insiders and he’ll win the General without them, too.”

Trump himself was, as usual, even more blunt on his Twitter feed:

So many self-righteous hypocrites. Watch their poll numbers - and elections - go down! — Donald J. Trump (@realDonaldTrump) October 9, 2016

This is not good politics in a conventional sense. Criticizing his intra-party rivals only serve to increase the salience of Republican Party disunity and make it more and more of a story.

But Trump himself is a thin-skinned and vindictive person, and his campaign chair, Steve Bannon, made bashing GOP congressional leaders a major sport when he was at the helm of Breitbart.com. So it’s entirely in character.

For the Republican Party as a whole, however, this is an absolute worst-case scenario. The House of Representatives map is so unfavorable to Democrats that it would take a miracle for the GOP to lose its majority. Closing out the 2016 election with a round of massive infighting is exactly just such a miracle. It’s the kind of thing you could imagine broadly demoralizing rank-and-file Republicans while confusing state parties and tanking turnout.