Some flourishes seemed to evoke Mr. Trump’s calamitous coronavirus briefings with reporters in the spring, when he alarmed his own supporters by screaming at routine questions about the pandemic.
At the same time, this was the matchup that Democrats envisioned when they elevated Mr. Biden above some two-dozen primary competitors: the amiable sidekick to the nation’s first Black president, a capital veteran who has transcended personal hardships, facing down an opponent rarely cited for feats of empathy and often openly hostile to the nation’s institutions.
The latter portion of that contrast is a discussion Mr. Trump has welcomed. Presenting Mr. Biden as a political lifer with little to show for his efforts, the president set out on Tuesday to continue the difficult work of running as the race’s true outsider while simultaneously controlling the levers of government.
“Forty-seven years, you’ve done nothing,” Mr. Trump said.
For months, Mr. Trump has been preparing his supporters for nothing short of abject humiliation for Mr. Biden on the debate stage, all but declaring (baselessly) that his opponent is beset by dementia and plying his followers with taunts of “Sleepy Joe” and often misleadingly edited social media clips of Mr. Biden’s verbal stumbles.
Of course, such overreach does not negate the trope that Mr. Biden is indeed an inconsistent debater at times. As he tends to a national polling lead generally in the mid to high single digits five weeks before Election Day, Democrats had suggested publicly that Mr. Biden merely needed to avoid catastrophe to consider the night a success. Surveys do indicate that most voters are already firm in their electoral intentions, leading strategists in both parties to question whether a single debate would make much difference.
Still, for liberals seeking a cathartic confrontation from their nominee after four years of Mr. Trump — and, more significantly, for the subset of voters disenchanted with this White House but hardly enthused about its alternative — Mr. Biden did enter the debate hoping to close the sale.
“So unpresidential,” he said of Mr. Trump’s conduct. But often, Mr. Biden struggled to negotiate the hail of interjections — and self-inflicted asides of his own that broke up any narrative momentum.