Have we gone, in the blink of an eye, from two dozen Democratic candidates to just three?

And is one of them—the guy who is leading the pack—not really sure why he’s running?

I say “just three” because Politico has decreed that there are only three Dems left with a real shot at winning the nomination.

I say “not sure” because the New York Times just ran a piece headlined “Does Joe Biden Want to Be Doing This?”

Journalists have a genetic urge to do State of the Race pieces after Labor Day (of the previous year!). To merely say the primaries are unsettled is to risk losing your commentator card. Hence the flurry of pronouncements about what will happen, months before the Iowa caucuses (which, as history has shown, can scramble everything).

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While President Trump waits to see who he’s running against, he has flatly declared that on one level he already knows: “The LameStream Media has gone totally CRAZY!...Our real opponent is not the Democrats, or the dwindling number of Republicans that lost their way and got left behind, our primary opponent is the Fake News Media.” (These tweets were in response to the “Amazon Washington Post” saying he had a terrible summer, providing a “vivid portrait of the president as seen by Trump’s critics—incompetent, indecisive, intolerant and ineffective.”)

Perhaps, just perhaps, Trump wants the media to be viewed as his primary opponent—because that potentially undercuts alliterative indictments like these—at least until he has an actual Democratic rival.

The Politico piece insists that “the bottom is falling out of the Democratic presidential primary. And the top-tier — no longer five candidates, but three — is becoming more insurmountable.”

And here come the polls: “Heading into the fall, only three contenders are polling above single digits: Joe Biden, Elizabeth Warren and Bernie Sanders.” Ergo, the rest are toast.

Politico allows that Kamala Harris and Pete Buttigieg are at the “periphery” of the top tier, but says Democratic strategists expect it to be highly unlikely that they will move up.

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Harris rose from 7 to 15 percent after her first-debate clocking of Biden, but has now slipped back to pretty much where she started. And Mayor Pete, another early media favorite, has been stalled for many weeks.

Beto, who’s reached the point where he’s dropping the F-bomb on CNN, is going nowhere fast after his initial Vanity Fair hype.

One Democratic operative quoted by Politico said Kamala or Pete can move up only if Biden collapses. And despite regular press predictions that he’ll do just that, Biden retains a double-digit lead not unlike what he had as the summer began.

I’d agree that the nominee will probably come from the Top 3, with one giant caveat: If someone else catches fire and wins Iowa—or finishes a strong second—that will scramble the equation. It was Barack Obama’s come-from-behind victory in Iowa that enabled him to overtake Hillary Clinton.

The Mark Leibovich story in the Times says Biden seems able to define himself only in opposition to Trump:

“‘I think it’s really, really, really important that Donald Trump not be re-elected,” Mr. Biden said, more of a rationale than answer. He then launched into a classic Biden roller derby of verbiage in which he listed all the reasons he found Mr. Trump so distasteful. He landed on a question to himself. "Could I die happily not having heard ‘Hail to the Chief’ play for me? Yeah, I could. That’s not why I’m running.”

Leibovich asks why the 76-year-old “really wants to be doing this right now — at this vicious moment in our politics and at this stage of his life?” And would he be doing it if Jeb Bush or Mitt Romney were in the White House.

“Um, I’m not sure, to be quite honest with you,” Biden said. “I hadn’t planned on running again.”

But I have trouble with the premise. If Biden believes Trump is doing severe damage to the country—and many Dems are telling the ex-VP that only he is a safe bet to oust the president—isn’t that rationale enough? Wouldn’t ending the Trump presidency make Biden a hero to Democrats, even if he’s not an exciting or ultra-progressive guy?

As someone who thinks the press has overhyped the gaffe narrative—Biden makes lots of them, that doesn’t mean he’s losing it—I continue to be troubled by his handling of the botched war story. That’s the one, as revealed by the Washington Post, where Biden conflated details of at least two different events in falsely claiming he pinned a medal on a reluctant Navy captain and mangled all kinds of other details.

Not only has Biden insisted he did nothing wrong, he told the NPR Politics Podcast that the episode has “nothing to do with judgment.”

“The details are irrelevant in terms of decision-making,” Biden said. “The fact that I would forget that it was Rodriguez [a major general] who was pinning a bronze star on a young man, it’s irrelevant to the point…It’s irrelevant and you know it.”

But what’s relevant is that Biden feels no need to express regrets for telling an untrue tale. Isn’t a main Democratic argument against Trump that he constantly plays fast and loose with the truth?

It may not matter politically, if only because most left-leaning pundits have given Biden a pass—saying his heart was in the right place—that they would never have granted Trump.

So even as the drumbeat begins for next week’s debate—when Biden will finally share a stage with Warren—he will remain the front-runner for the foreseeable future.