Amid Biden worries, can any Democrat beat Trump?

Cory was the new Kamala. In the second Democratic debate, the New Jersey senator took up where the California senator left off — with an aghast look into Joe Biden’s past. Booker demanded that Biden own up to and defend his major role in 1990s criminal justice legislation that helped lead to mass incarceration.

“There are people right now in prison for life for drug offenses because you stood up and used that ‘tough on crime’ phony rhetoric that got a lot of people elected but destroyed communities like mine,” Booker said, referring to Newark.

Kirsten was also the new Kamala. But then Bill de Blasio was the new Kamala and Julián Castro was the new Kamala and even Kamala was the new Kamala, all of them determined to throw Biden off his stride and accelerate their own march forward in the process.

Unfortunately for them, Biden wasn’t the old Biden — not exactly. He was better prepared. He was more composed. He obviously expected every attack and had clearly rehearsed his responses, so that he never had the hapless, helpless look of his prior outing. If his rivals expected Wednesday night to be the beginning of the end for him, they were wrong.

And yet Biden hardly put the doubts about his sturdiness and stamina to rest. I so hoped and I so want to say otherwise, because I believe him to be a decent man, because he’s talking more sense than many of his starry-eyed adversaries, because it may well be that among the voters who will decide this election in the places where President Trump plans to fight hardest, Biden is a better — or at least safer — bet than any of the other candidates getting more than 2 percent in national polls right now.

But there’s that way in which he trails off at the end of a sentence or an argument, all the little hiccups en route, the messy seams connecting one thought to the next, the demeanor that falls into a gray area between engaged and fully animated. If Booker and de Blasio traffic in too many exclamation points, Biden traffics in too many ellipses.

I’m focusing so much on him because so much of the focus was on him. The debate in Detroit among the second group of 10 Democrats wasn’t principally about health care, immigration, race relations or climate change — not in terms of the question foremost on many observers’ minds. The debate was about whether the man at the prime lectern, with a very big lead, had lost his famous ebullience and parted with his former confidence.

Biden’s ability to keep from sweating and to keep smiling was no mean feat under the circumstances.

A few facets of Biden’s candidacy came into sharper relief. One was how much he’s riding — and counting — on his association with President Barack Obama and how complicated that tactic is.

The debate also made clear how untenable Biden’s initial, preferred approach to this race was. He wanted to float above the fray, attacking Trump rather than brawling with his fellow Democrats. He wanted to seem bigger. He wanted to be sunnier.

But his rivals were never going to let that happen, and they didn’t. They insisted that he scrap with them, on their level.

I kept looking for an assurance that he couldn’t deliver, listening for a lyricism that he couldn’t manage, praying for a sign that after two miserably failed presidential candidacies, the third time would be the charm for Biden and our amulet against Trump. I didn’t get that guarantee from him, but then I didn’t get it from anyone else, including the 10 candidates who debated the night before.

Is it possible that the Democrats have an overflow of talent but no one who’s precisely right? I worry.