I remember shaking my head, on the day that Donald Trump announced, when NPR’s Mara Liasson declared that this would be the best day of his campaign and it was downhill from there.

Liasson cheerfully admitted she was wrong on my show, but she had plenty of company. Most of the media establishment seemed to fall into two camps: those who were skeptical that Trump was anything more than a sideshow, and those who attacked him as a clown and a charlatan.

Fast-forward to this past weekend when Chris Wallace, having just interviewed Trump for “Fox News Sunday,” said: “I know all of us dismissed Trump, early on, all of the so-called experts.” But after their sitdown, Wallace said, “I am beginning to believe he could be elected president of the United States.”

The so-called experts are starting to face reality. Joe Scarborough said yesterday that anyone who believes Trump can be stopped if he wins Iowa is “dreaming.”

None of this means Trump will win the nomination, let alone the general election.

But it means the media’s state of denial over a guy who has led the Republican polls for three solid months is drawing to a close.

National Review has taken notice, with the headline “The Establishment Thinks the Unthinkable: Donald Trump Could Win the Nomination”:

“Now, long-time GOP strategists who were expecting Trump’s act to wear thin a couple of months ago worry that he can’t be stopped, or at least that he has a significant chance of winning the nomination.”

Ya think?

I have spent months arguing with panelists on “Media Buzz” and other Fox shows who have mocked and minimized Trump. Having watched and interviewed him in New York since the 1980s, I knew Trump was a tough customer, a veteran of the city’s tabloid wars who became a reality-show star as well as a brand-name builder.

Pundits who thought Trump was all bluster were stunned to learn that he had struck a deep chord with many GOP voters. All the things that journalists have learned to value—political experience, policy depth, an organized ground game—didn’t matter with Trump. He sensed what they failed to see, that voters were so ticked off at Washington and political gridlock that they yearned for a tough-talking outsider—and he boasted about having been a wealthy insider who played the game.

One by one, the pundits are caving.

Veteran Republican strategist and CNN commentator Alex Castellanos told Political Wire, “I’ve resisted the idea that Donald Trump could and would become the Republican nominee. Unhappily, I’ve changed my mind.”

Mark Leibovich profiled Trump in the New York Times Magazine, writing: “Initially, I dismissed him as a nativist clown…I was, of course, way too incredibly serious and high-­minded to ever sully myself by getting so close to Donald Trump.”

Even the Huffington Post has now run a piece titled “It’s Time to Admit: Nobody Knows Anything About the 2016 Campaign.”

The headline should have been that the Huffington Post didn’t know anything about the campaign. This is the liberal website so convinced that Trump was a bozo that it pulled the stunt of relegating him to the Entertainment section.

“Trump’s rise and sustained competitiveness in the race has been a trick that just about nobody -- perhaps not even the candidate himself -- thought that he could pull off initially, when those old rules still seemed to be in place,” the piece says.

Just about nobody? Lots of people figured it out months ago. This story amounts to a belated and grudging correction—and it ran in the Politics section.

Now I’ve heard all the theories about why Trump will still implode: His unfavorable numbers are too high. He’s hit his ceiling and it won’t be enough when the race is winnowed to three or so candidates. Voters will get serious by Iowa and New Hampshire and pick an actual commander-in-chief.

Well, any of those things could happen. But we’ve been through all these episodes that were supposed to end Trump’s campaign (about Mexican immigrants, John McCain, Jorge Ramos, the anti-Muslim questioner and on and on) and he’s still going strong.

Many conservative columnists continue to rip Trump as a fake conservative, but many voters apparently like his mix of right-wing ideas (tax cuts, immigration crackdown), moderate ideas (protect Social Security and Medicare) and even a couple of liberal ideas (taxing hedge-fund titans).

It’s been a humbling experience for media people who’ve been dead wrong about the 2016 campaign. As the Huffington Post says, “So many supposed experts have been so wrong about so many facets of the race.” A little humility might be in order.

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Howard Kurtz is a Fox News analyst and the host of "MediaBuzz" (Sundays 11 a.m. and 5 p.m. ET). He is the author of five books and is based in Washington. Follow him at @HowardKurtz. Click here for more information on Howard Kurtz.