"The Joe Biden Death Watch," Frank Bruni, The New York Times

Former Vice President Joe Biden in Gaffney, S.C., on Aug. 28.Mike Belleme for The New York Times

By Frank Bruni

To go by much of the coverage of Joe Biden lately, he’s a candidate flirting with disaster, fumbling toward mortification, his footing unsure, his purpose unclear, his political demise just a matter of time. And maybe that’s so.

But the Biden story so far has actually been one of surprising durability. He led the Democratic field when he entered the race more than four months ago. In the latest surveys, with the exception of one outlier a week and a half ago, he leads the field still — by double digits in several polls.

He had an awful first debate; his lead held. He had a mediocre second debate; ditto. His oratorical errors multiply. Still he’s the front-runner.

So is the negative media coverage a reflection of our own restlessness and insistence on a story line less static than the current one? To a minor extent, yes.

But we’re also flagging undeniable shortcomings of Biden’s that are likely to become even more apparent as the exhaustion of a long campaign kicks in. They’ll also become more noticeable to voters, many of whom aren’t paying especially close attention yet. We’re rightly sending up a flare about that.

Biden doesn’t project the energy that he once did. He seems less sharp, less crisp. Maybe that’s vitally important, maybe it’s of negligible concern: Voters can and should decide which. Either way, it would be derelict of us to ignore it.

But that’s precisely what many Democrats want us to do. They feel that unflattering appraisals of any of the most likely nominees are a crack in party solidarity and a gift to Donald Trump. I know because some of these Democrats are readers of this newsletter, and you’ve contacted me to urge me and my colleagues to go easy on the party’s prime contenders in light of the stakes: four more years of Trump.

I don’t think that’s an appropriate tack journalistically, and I don’t think it’s a wise one tactically. A rigorous vetting of the primary candidates is the route to the best nominee, and it’s not as if flaws that we turn a blind eye to now will then be missed by Trump and his allies. They’ll go in for the kill, and the primary process is partly about discovering how well various Democratic candidates will respond to that. We can’t know unless they’re navigating similar criticisms before the general election.

What we in the media do need to be careful about is reducing any of the Democratic candidates to a single narrative or letting one facet of their bids eclipse all others, because that prevents a candidate from getting his or her full message out and the public from hearing it.

We arguably did that with Hillary Clinton and her emails four years ago. Let’s not do that with Biden’s gaffes this time around.