Two Appearances, Two Starkly Different Bidens

Millions of Americans saw one Joe Biden on Thursday night: halting, hesitant, meandering and looking burdened by every one of his 81 years. Democrats were aghast.

Fourteen hours later, a smaller number of television viewers saw a different Joe Biden: forceful and confident, landing political punches on former President Donald J. Trump with ease. Democrats in the room cheered.

Mr. Biden and his allies no doubt wished the appearances had been delivered in reverse order. The tepid and weak debate performance by Joe Biden One caused an immediate freak-out among those determined to see Mr. Trump lose in November. Some publicly broached the unthinkable: a new candidate.

The afternoon appearance in a fairground warehouse in North Carolina was seen by far fewer people, and seemed unlikely to immediately quell the hand-wringing among Washington consultants, media pundits and ordinary voters.

And yet, in the middle of the panic, Joe Biden Two showed that, even after five decades in public life, he can still pump his fist in the air, stir a crowd to cheer and perhaps inspire an unwieldy coalition to vote for him one more time.