Joe Biden just may be the keepsake that endures.

The other two went at it Thursday night, quarreling over the meaning and morality of a wine cave, in an exchange that distilled the Democratic primary’s broader tension between pragmatism and purity, compromise and idealism. Biden was careful not to be drawn too far into it and, during other stretches of the debate, stood back.

Why wouldn’t he? For all the worry because he sometimes stutters, for all the concern because he occasionally sputters, for all his corny locutions (“malarkey”) and reflexive conversation fillers (“here’s the deal”), the former vice president has almost consistently maintained a lead over his Democratic rivals in national polls since he announced his candidacy last April. He has recently gained ground in Iowa, the state that votes first, meaning he may avoid what had been looking like a candidacy-imperiling embarrassment there.

He has survived salvos from critics and messes of his own that were supposed to halt or at least hobble him: the attention to his crossing-the-line physicality with women; the flip-flop about public funding of abortions; the back-and-forth with Kamala Harris about busing; the moment at the fifth Democratic primary debate when he seemed to forget either that she was in the Senate or that she was black.

All of that supposedly made him look weak. But none of that appreciably weakened him.

And at the latest debate, he performed better than before — which may not be saying a lot but is saying something. He still can’t speak in a straight line, instead zigging and zagging: If he were a car, his tires would constantly scrape the curb and his hubcaps would probably pop off.

But they stayed on this time around. Biden, 77, seemed more relaxed and confident, and he radiated his trademark warmth. It’s difficult not to like him. And it’s time to give him his due.

So many of us haven’t, and I’m as guilty as anyone. In past columns I urged him not to run — citing his unsuccessful previous presidential bids, his age, his eccentricities and his outright flaws — and doubted his ability to go the distance. I joined other pundits and political analysts in treating Biden’s front-runner status as fictive or inevitably fleeting and as the bequest of simple name recognition.

We decreed that other contenders — Harris for an instant, Warren and Buttigieg for longer, even Bernie Sanders of late — had momentum. Biden had vestigial good will, which we regarded as a less flashy and flimsier commodity.

When we examined Biden, we saw warning signs. Look at that light schedule! Check out those anemic fundraising numbers! Sure, many Democratic voters deemed him the most electable alternative at a juncture when snatching back the White House mattered infinitely more to them than any romance with a figure fresher and more inspiring than he is. But would they stick? And could he last?

So far, so good — or, rather, so Biden, which in Thursday night’s debate meant a quizzical reference to Winston Churchill, some endearingly loose banter with Sanders and an overarching aura of sheer good-naturedness.

When one of the moderators, Tim Alberta of Politico, brought up the subject of age, Biden said: “Look, I’m running because I’ve been around. All my experience. With experience, hopefully, comes judgment and a little bit of wisdom.”

Alberta noted that if Biden won the presidency, he’d be 82 at the end of his first term. “Are you willing to commit tonight to running for a second term?”

“No, I’m not willing to commit one way or another,” Biden said without pause, to supportive laughter from the audience. “Here’s the deal. I’m not even elected one term yet, and let’s see where we are. But it’s a nice thought.” It was a nice answer.

Moderators gave him ample opportunity to stumble, challenging him, for example, on the Obama administration’s failure to close Guantánamo Bay and its exaggeration of progress in the war in Afghanistan. He had answers at the ready and exhibited zero discomfort.

While he was evasive about a few topics, he was emphatic about his disagreement with Sanders and Warren on “Medicare for All.” And he leapt into the fray to explain that he finds that plan exorbitant and far-fetched. “I’m the only guy that’s not interrupted,” he said. “All right, I’m going to interrupt now.” This from a man who, at a previous debate, cut himself off even before moderators did.

I maintain serious reservations about him. Thirty-six years in the Senate and eight in the vice presidency add up not just to enormous experience but also to a sprawling record that’s a gold mine for detractors. He undeniably lacks the vigor he once possessed.

And President Donald Trump’s cynical airing of questions about his past dealings with Ukraine — and about the lucrative position that his son Hunter had on the board of the natural gas company Burisma — remains a potential liability for Biden, who still hasn’t found and delivered the perfect rebuttal.

But journalists may not have the right antenna for how this is playing out. When Biden admonished a man in Iowa who credulously parroted Trump’s line of attack, many political analysts pronounced him imprudently thin-skinned and unattractively defensive. But many voters surely saw him as authentic, relatable — a loving father and decent person disgusted with the nastiness coming his way. There’s an upside to trading a safe, conventional political script for something rawer. Trump demonstrated that in 2016.

And Thursday night, Biden reasserted the fundamental generosity of spirit that separates him from Trump and is like a tall, cold glass of water to Americans thirsty for decency. “I refuse to accept the notion, as some on this stage do, that we can never, never get to a place where we have cooperation again,” he said, making a pitch for bipartisanship. “If that’s the case, we are dead as a country. We need to be able to reach a consensus. And if anyone has reason to be angry with the Republicans and not want to cooperate, it’s me — the way they’ve attacked me, my son and my family.”

He got fresh reason during the debate, when Sarah Huckabee Sanders, the former White House press secretary, sent out a tweet that ridiculed his stutter. She deleted it — and apologized — after he asked her where her empathy had gone, a question I assumed was rhetorical. It died on the altar of Trump, where too many other Republicans sacrificed their principles, too.

Biden glows in comparison. He almost looks shiny.

This article originally appeared in The New York Times .