Mike Bloomberg has had the luxury, available only to billionaires, of creating his own campaign universe—floating above the fray, mostly avoiding journalists, carpet-bombing the airwaves with ads.

Well, that ends tonight, at least briefly. On a stage in Las Vegas, the Wizard of Oz will have to come out from behind the curtain and engage with the mere mortals slogging it out for the nomination.

And Bloomberg will have to confront the criticism of his record that the press has unearthed in what might be called vetting on steroids, packing loads of negative info and self-inflicted wounds in the space of 10 days.

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That became official yesterday when Bloomberg surged into second place, at 19 percent, in a poll for NPR and the PBS “NewsHour.” Bernie Sanders led the pack at 31 percent, with Joe Biden (15), Elizabeth Warren (12), Amy Klobuchar (9) and Pete Buttigieg (8) in the second tier. With Nevada and South Carolina approaching, this shows that Klobuchar and Buttigieg have not been able to convert their Iowa and New Hampshire showings into a competitive position in larger and more diverse states.

Although Bloomberg is a national figure by virtue of running New York City for a dozen years, the MSNBC debate amounts to a reintroduction for many millions of Americans. And for all the apparent effectiveness of the “Mike Will Get It Done” ads, the truth is that Mike isn’t a great orator or stellar debater.

But Bloomberg doesn’t have to be Lincoln or Douglas, he just has to survive with a minimum of cuts and bruises. Aides say he has been practicing in mock debates but that his rivals have honed their skills during the past eight faceoffs.

The 78-year-old candidate has been positioning himself as the only adult in the room who can beat Trump, but in his years of sparring with reporters he has also turned testy over questions he doesn’t like.

The world will see how thick his skin is. But obviously many Democrats have been willing to overlook what they see as Bloomberg’s flaws—he is after all a onetime Wall Street trader first elected as a Republican—in the belief that he’s their best shot at ousting Trump.

Sanders, who has been pounding Bloomberg, and the others will have no shortage of material. Every day, it seems, another video surfaces of Bloomberg saying things that are politically incorrect or downright offensive. First there was him saying young blacks should be thrown up against a wall as a way of getting guns off the streets, and blaming the 2008 financial collapse on the end of redlining by banks. Now there’s tape of Bloomberg saying it doesn’t take much in the way of smarts to be a farmer or operate machinery.

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The twin blows of the Washington Post detailing his past sexist and profane remarks to women and the New York Times saying he uses his charitable giving to buy political support would wound any candidate. But Bloomberg, of course, is not just any candidate, and his record-shattering spending has been a surprisingly strong political shield.

Everything had to go break right for Bloomberg’s skip-the-early-states strategy to work (and I’m among those who were skeptical). Joe Biden had to get clobbered and Bernie Sanders had to keep rising, setting off a panic among the Dems for a moderate liberal who could defeat the president.

When you’re back in the pack, the press scrutiny is lighter. Klobuchar couldn’t name the president of Mexico at a recent Latino forum, and there are reports she then left early, but it barely caused a blip. Bloomberg doesn’t get a pass on stop-and-frisk or any of his other policies that are less palatable to liberals and minorities than gun control and climate change.

But while we’re hearing plenty (especially from Bernie) about a rich guy trying to buy the election, it takes more than money. Otherwise Tom Steyer would have the nomination locked up, and Jeb Bush would have won last time. Bloomberg’s ad barrage, backed by hundreds of millions of dollars, resonate because he has a solid record as mayor of the nation’s largest city. Even Donald Trump has praised him in the past, before trying to transform him into a height-challenged wannabe.

It’s healthy for the process that Bloomberg will now have to deal with challenges from moderators and political rivals. How he fares could well determine his chances on Super Tuesday and beyond.