I noted that the last Republican debate was the moment when Marco Rubio suddenly turned the tables on Donald Trump. The key exchange was when Rubio took the accusation of repeating himself, which Chris Christie has used against him, and turned it against Trump. What made this so effective is that Rubio was smiling and confident while Trump looked outraged and rattled, which is not his most flattering look.

But it turned out Rubio was just getting started. Over the weekend, he has been getting under Trump’s skin with a series of personal jabs and open mockery. He has been reading Trump’s mean tweets — mocking his copious misspellings and concluding that he “must have hired a foreign worker to do his own tweets” — then talking about Trump having a backstage meltdown and wanting a full length mirror, “to make sure his pants weren’t wet.”

At another event, he went on to mock Trump’s spray tan.

And he shut down a heckler by presenting him to the crowd as “the valedictorian of Trump University.”

This was a way of hitting Trump for his fraudulent real estate seminars, and along with the rest of the jabs, it serves a broader theme of portraying Trump as a “con man” trying to take over the Republican Party.

This last weekend signals a big change in strategy for Rubio and one that a lot of people were criticizing him for not doing earlier. But here’s the genius of it: there is no narrative Americans love more than “underdog turns tables on bully.” Rubio is putting himself in the Ralph Macchio role in “The Karate Kid.”

Which means that Trump is this guy.

Hey, if the shoe fits.

Call it the 1980s Underdog Movie Theory of the Republican Primaries. This was practically its own genre. It was not just “The Karate Kid.” It was a theme in “Back to the Future” — in the sequel, the 1985 alternate universe version of Biff Tannen was actually modeled on Trump — and in “Top Gun.” (Though that’s a better analogy for the Rubio-Cruz relationship, with Cruz as Iceman.) It was all of the Rocky movies. After Rubio’s Texas debate performance, someone tweeted:

Envisioning an ’80s-style movie montage where Rubio spent all week boxing a side of beef. #GOPDebate— Christian Schneider (@Schneider_CM) February 26, 2016

Rubio certainly found the “Eye of the Tiger.” And yes, I know I’m mixing up my Rocky movies, but honestly, was there all that much difference between them?

Actually, this is a darker variation of the narrative in which the hero has to learn to fight the villain on his level. So the guy with a command of policy whose brand is his positive, optimistic style has had to learn how to win by using his opponent’s weapon of ridicule.

You know what last week was? It was that moment in “The Untouchables” when Sean Connery says to Kevin Costner, “What are you prepared to do?” And he eventually realizes he needs to fight the Chicago way: “He pulls a knife, you pull a gun. He puts one of yours in the hospital, you put one of his in the morgue.”

Over the past few days, Rubio has certainly been sending Trump to the burn unit.

Should Rubio have done this earlier? Ah, but then he would be the Heel, not the Underdog.

You know what also reached its height in the 1980s? Professional wrestling. I didn’t watch it because you don’t get to be an effete, intellectual elitist by watching WWE. (I was too busy with the math team.) But I had friends who watched it, so I know that Vince McMahon had perfected the fake theatrics in which you build up the Heel, the contemptuous blowhard the audience loves to hate — basically, the Trump role. But Trump knows WWE, and he should have seen the problem. In the end, the only reason you build up the Heel is so the crowd can cheer when the hero takes him down.

Up to now, Rubio has campaigned on sincerity, uplift, and mastery of policy details. If he had started out slinging sharp one-line put-downs like this, he would have risked looking petty and classless. And he really would have had to worry about taking it too far.

But by the time we’ve all watched Trump insult everybody for six months, we are so ready to see someone give Trump a taste of his own medicine that Rubio can now get away with just about anything, as long as it’s funny and really zings. We’re at the point in the story where we really want to see George McFly lay out Biff Tannen.

And we’re finding out that Rubio has been holding back on us. Apparently he spent his high school years playing a game with his friends where he traded insults to see who could come up with the best one. Basically he’s now doing that with Trump, and winning. This also explains how Rubio can do it with such a lighthearted smile. He has the manner of a guy just kicking back with his friends, trading the equivalent of “yo mama” jokes.

All of this seems, finally, to be throwing Trump off balance.

The best commentary on the Republican primary is still Dan McLaughlin’s long analysis of the election in terms of military strategist John Boyd’s theory of the “OODA Loop” decision-making cycle. He explains how Trump came in and disrupted all the normal rules of campaigning, forcing the other candidates to adapt. Since presidential campaigns normally prioritize caution, it took them a long time to adapt — basically, up until now. But McLaughlin points out that Trump is just playing the same media game he’s been perfecting for 35 years, and while he has forced everyone else to adapt to his methods, he himself does not seem to be able to adapt to changing circumstances. He is likely to just keep on doing what has worked for him all along, heedless of the fact that it’s no longer working.

Rubio is making Trump look like a trust-fund baby who can dish it out but can’t take it.

We’ve been seeing some evidence of that. After the Texas debate, Trump was out there the next day on Twitter, still trying to drive the narrative by labeling Rubio a choker, or rather a “chocker” — but you see what I mean? It doesn’t work any more because Rubio has turned that into a meme that makes Trump look bad. Rubio is now driving the narrative against him.

This also explains the advantage Rubio has over Cruz. At the Texas debate, Cruz was still mostly trying to attack Trump for inconsistencies on conservative policy. But anyone who has tangled with Trump’s supporters knows that a lot of them either don’t know or don’t care about policy (or consistency). Trump’s campaign is about his personality and the Trump mythology of his self-made business success and tough negotiating skills. That’s what Rubio is hitting by making Trump look like a trust-fund baby who can dish it out but can’t take it, and like a con man with a string of failed, over-hyped ventures.

Is he doing this too late? Maybe. This all assumes Rubio can invert the narrative in time — that this is that moment about two-thirds of the way through the movie when the hero suddenly begins to turn it all around at the last minute. Yet there’s no guarantee of a happy, Hollywood ending.

But if Rubio manages this, he becomes the big hero. A presidential campaign puts candidates through a series of crises to see who can rise to the challenge. In this case, Rubio needed to move out of his comfort zone, away from his preferred political persona, and show he can face an unconventional rival and adapt to him. If he does this, then he earns the special gratitude of those of us who are appalled at the concept of Trump taking over the Republican Party. It means that a lot of people who might have been inclined to accept Rubio reluctantly, as the least bad option (he is after all, still a politician) will embrace him enthusiastically as our champion, as the Trumpslayer who saved the party and the movement.

Which is to say that he just might earn that nomination, just like any good protagonist in an underdog narrative.

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