(CNN) It's been more than 72 hours since a photo of two men -- one in blackface , the other in the white robes of the Ku Klux Klan -- on the medical school yearbook page of Democratic Virginia Gov. Ralph Northam went viral. In that time, virtually every major figure within the Democratic Party in Virginia and nationally (not to mention Republicans) has called for Northam to step aside.

And yet, he remains on the job -- and, according to sources, continues to believe he can somehow weather the storm the picture and his subsequent news conference trying to explain it have caused.

In each episode of his weekly YouTube show, Chris Cillizza will delve a little deeper into the surreal world of politics. Click to subscribe!

How? Why?

The answer to these questions is simple: because he can.

It's very hard to get rid of a governor who hasn't committed an actual crime. And as awful as that picture is -- Northam now claims he is not actually in the photo, although on Friday night he said he was -- it's not evidence of any sort of crime. Already, the speaker of the Virginia state House -- a Republican -- has made clear that impeaching Northam is very, very unlikely

Northam knows this. And he also knows that past political history suggests that if you can survive the first 96-ish hours after a scandal, you can often survive it. There are plenty of reasons for this -- one is the high bar for removal from office, another is the incredibly short attention span of the political media and the average news consumer -- but there are several examples, of late, that might well boost Northam's optimism.

The most glaring is, obviously, President Donald Trump himself. During the 2016 campaign, Trump said and did a number of things that would have ended any normal campaign. More than a dozen women accused him of inappropriate behavior. He paid off two women who alleged they had affairs with him in the mid-2000s. And most notably, he was caught on tape making a series of lewd and misogynistic remarks on an "Access Hollywood" bus. Trump denied the allegations of sexually inappropriate behavior. He apologized for the "Access Hollywood" tape and then subsequently dismissed it all as "locker room talk." And he not only stayed in the race, but he won.

While not a politician, Judge Brett Kavanaugh, Trump's pick for a Supreme Court vacancy last year, followed a similar blueprint after a woman named Christine Blasey Ford alleged that he had sexually assaulted her when they were both in high school. Kavanaugh denied the whole thing and insisted he was the target of a liberal conspiracy. ( There was no evidence Blasey Ford was motivated by partisanship.) While the vote was close, Kavanaugh was confirmed to the Supreme Court.

And there is the case of Rep. Steve King, an Iowa Republican, who resisted calls for him to step aside after comments to The New York Times that seemed supportive of white nationalism. While King was stripped of his committee assignments by his fellow Republicans, he simply refused to walk away -- and the political world moved on. King, of course, may face an eventual reckoning with voters next year, as he faces a serious primary fight.

You could look at those three examples -- plus a variety of politicians, mostly Democrats, who resigned very quickly after a scandal broke and, in retrospect, might have been able to hang on -- and think: I can do this.

The key word in that last sentence is "think." Yes, Northam may think he can survive this, but there are several extenuating circumstances which suggest that, well, he can't. Consider:

1. Northam initially said it was him in the picture -- although he wouldn't say whether he was the one in blackface or the Klan robes -- before recanting less than 24 hours later to insist it was definitely not him. Huh?

2. The picture was from Northam's medical school yearbook, meaning he was in his mid-20s when it was taken. Also, this was 1984. Not 1954.

3. In his Saturday news conference, Northam acknowledged that he had darkened his face to resemble Michael Jackson for a dance contest in 1984.

4. Asked whether he could still moonwalk, Northam appeared to be preparing to actually do the dance move -- at the news conference! -- until his wife stopped him.

That quartet of factors make Northam's stance impossible to maintain -- particularly given the zero-tolerance policy the Democratic Party as adopted toward past transgressions in this age of Trump and the #MeToo movement. Having someone who has said and done what Northam has said and done over the past three days in a position of power is simply untenable for Democrats desperately hoping to retake the White House in 2020.