It seems ages ago, but recall when the second presidential debate was deemed the sink-or-swim moment for the candidacy of Donald J. Trump. The slobbering sex tape had just come out, causing many fearful Republicans to dis-endorse him. One more astounding meltdown on the debate stage and Trump would be out (though how that could happen was never made clear).

The post-debate consensus held that Donald stopped the heavy bleeding and Hillary Clinton was cautious. She didn’t bait him with anything new and left the heavier fire for the second half, thus helping the Trump candidacy live to self-destruct another day.

That’s exactly what happened. And whether by design or not, that’s exactly what Clinton and other Democrats should have wanted. The importance of keeping Trump at the top of the Republican ticket could not be overstated.

Democratic wish come true, Trump again bubbled up from the black lagoon and turned his malevolence on the Republican Party. Unleashing new chaos in the electoral ranks, he blasted Republicans who had broken with him over the tape. He poured hot new insults down on House Speaker Paul Ryan and Sen. John McCain. Cowed by the display, some Republicans who had disgraced themselves by not dropping Trump long ago disgraced themselves again by pedaling back.

In sum, Republican candidates are faced with an unenviable choice. They can back a candidate whom most independents and many fellow Republicans regard as repellant. Or they can drop him and risk the wrath of Trump supporters vowing revenge on any Republican disloyal to The Donald. Some Trumpsters are threatening to not vote for down-ballot Republicans.

With national polls shifting decidedly in Clinton’s favor, Democrats feel free to put resources in red states once considered fairly out of reach. Georgia and Arizona are now very much in play.

The Democrats’ strong hope of restoring a Senate majority has grown stronger thanks to The Donald. As a result, Republicans Pat Toomey of Pennsylvania and Richard Burr of North Carolina face titanic battles — titanic as in the RMS Titanic. And the previously impossible Democratic dream of taking the House now seems possible.

GOP leaders should draw no comfort in a poll suggesting that voters are making little distinction between Republicans for Trump and those who renounced him when times got tough. As for the second group, Trump promises to make their political lives as painful as possible. One thing The Donald knows how to do is deliver pain.

Borrowing from the 12 days of Christmas, Democrats may be planning the 12 days of October Surprises. The month began with the revelation that Trump may not have paid federal income taxes for close to two decades. Then came the gift-wrapped tape in which Donald spoke freely of his animal magnetism with women and willingness to grab that which is not offered. The month is still young.

This cannot be a happy time for those who value a vigorous political culture, regardless of where they hang their partisan hats. We need two functioning political parties, each offering a reasonable alternative to the other.

The bright spot here is that an electoral rout might force Republicans to do something they should have done long ago — cast off the delirious mobs of their so-called base and replace them with independents open to sane conservative arguments. Many principled conservatives are now talking along these lines. Some have gone so far as to herald a Trump-driven electoral collapse as the shock therapy their party needs.

Dr. Bornstein, please keep Donald healthy. He can’t lose it if he’s not in it. America needs Trump to plunge headfirst into the black lagoon — and stay there.

Froma Harrop is a syndicated columnist. Follow her on Twitter @FromaHarrop. She can be reached by email at: fharrop@gmail.com.