In a crowded debate, you can tell which candidates are seen as the greatest threat because they take the most incoming fire from their rivals.

During the Republican presidential primary debate on Wednesday night, that person wasn’t Ron DeSantis, who was once considered Donald Trump’s greatest threat, but Vivek Ramaswamy, a 38-year-old political upstart with little chance of actually securing the nomination.

Watching the DeSantis campaign collapse has been an extraordinarily edifying spectacle.

There would have been no DeSantis without Trump. Trump endorsed DeSantis for governor of Florida when DeSantis was struggling against a strong Republican opponent for the party’s nomination. DeSantis rode Trump’s endorsement to victory.

So, there was always something in the DeSantis campaign that knew that he was Macbeth coming to kill his king. The only problem was that DeSantis had ambition, but not the bloodlust. He lacks the courage, which is ironic given that DeSantis wrote a book before his run entitled, “The Courage to Be Free.”

Instead of making the case to voters that Trump was unfit, he is counting on Trump’s martyrdom being his downfall. His gamble has yet to pay off.

In addition, DeSantis has a chronic personality problem. He simply doesn’t connect with people. He smiles the way a Doberman bares its teeth: it feels forced, aggressive and dangerous. You feel like you should retreat from it. And when he’s not forcing a smile, he reflexively scowls.

He has a resting wince face.

He is not only emotionally aloof, but completely detached. He abides in aggression because the rest of the emotional range has either atrophied or failed to develop in the first place. In fact, during debate prep in 2018, one of his advisers told him that on the debate stage he would need to write “LIKABLE” in all caps at the top of his note pad.

On Wednesday, DeSantis dispensed with that advice. He leaned into the aggression. But no one engaged. No one even responded. He was largely ignored by the other candidates, and the only thing that cuts deeper than disparagement is indifference.

Instead, Ramaswamy was the target onstage, and he ate up the attention.

Every since the rise of Barack Obama and Republicans’ unseemly reaction to it, the party has entertained exotica. In 2011, Herman “9,-9,-9” Cain surged in the G.O.P. field for a while. In 2015, Ben “no Muslims as president” Carson led Trump in the polls for a moment.

They are the amuse-bouche, the tasty appetizer before the party gets serious and sits for the meal.

Now, it is Ramaswamy’s turn.

At one point, Chris Christie attempted to insult Ramaswamy by saying that “the last person at one of these debates who stood in the middle of the stage and said, ‘what’s a skinny guy with an odd last name doing up here,’ was Barack Obama, and I’m afraid we’re dealing with the same type of amateur.”

Ramaswamy glowed at the comparison and shot back: “Give me a hug just like you did to Obama, and you’ll help elect me just like you did to Obama too.”

Let’s be clear: Vivek, you are no Barack.

You have a shallow, CliffsNotes understanding of the issues, but because you speak with speed and confidence, polished diction and a toothy grin, the incoherence is disguised by the delivery. Ramaswamy is the kind of person who gets hired for charisma rather than competence.

At points, it seems obvious that he is being intentionally contrarian, outlandish and provocative in his proposals and pronouncements in order to provoke a reaction and garner more attention. In doing so, he is the personification of click bait.

He is also positioning himself as inseparable from Trump. Not a competitor of Trump, but a superfan. He doesn’t want to replace him, he wants to merge with him. Ramaswamy is so close to the former president that he’s like the joey in the pouch to Trump’s kangaroo.

This ingratiates him not only to Trump’s voters but to Trump himself, because Trump appreciates nothing more than devotion and loyalty.

This had to hurt DeSantis. He is consumed by a class complex. As DeSantis wrote in his book, he was a “blue-collar kid,” an every-Sunday-service Catholic, who made his way to the Ivy League where he believed his wealthy classmates looked down on the working class as not “sufficiently sophisticated.” He is still fighting to prove that he belongs, to prove that his worldview is not only valid but superior.

And along comes Ramaswamy, also wealthier and more polished than him, to once again steal his shine, to make him feel small and insignificant.

There were points during the debate when Ramaswamy sparred with Mike Pence and Chris Christie while literally looking past DeSantis as if he wasn’t there.

DeSantis didn’t crash and burn Wednesday night. He made no real errors. He stayed on message and forcefully delivered his points. But the debate delivered its own point to him: His star is setting while another rises.