After last week’s debate disaster, some Democrats are trying to circle the wagons to protect President Biden, noting that Barack Obama lost his first debate as an incumbent president, too.

But this one doesn’t pass the smell test. Mr. Obama wasn’t 81 years old at the time of his debate debacle. And he came into the debate as a strong favorite in the election, whereas Mr. Biden was behind (with just a 35 percent chance of winning).

A 35 percent chance is not nothing. But Mr. Biden needed to shake up the race, not just preserve the status quo. Instead, he’s dug himself a deeper hole.

Looking at polls beyond the straight horse-race numbers between Mr. Biden and Donald Trump — ones that include Democratic Senate candidate races in close swing-state races — suggests something even more troubling about Mr. Biden’s chances, but also offers a glimpse of hope for Democrats.