Riding a wave of several hundred million dollars worth of advertising – and despite the onslaught of negative information about his opinions on race, stop-and-frisk, and his past support for Republicans – former New York City Mayor Mike Bloomberg has climbed to second place in some recent national polling of Democratic presidential candidates.

As a result, Bloomberg won a place on stage at Wednesday night’s Democratic presidential candidate debate in Las Vegas.

But though he was the last candidate invited, Bloomberg is certain to be the center of attention. Indeed, the only prediction I’m confident to make is that the TV ratings for the Las Vegas debate will be significantly higher than other recent Democratic debates.

BERNIE SANDERS SLAMS BLOOMBERG AT LAS VEGAS TOWN HALL, SAYS BILLIONAIRE TRYING 'TO BUY THIS ELECTION'

Not just political reporters, but audiences anticipate some kind of cage match between successful entrepreneur Bloomberg, self-described democratic socialist Sen. Bernie Sanders of Vermont, and analytic advocate for structural change Sen. Elizabeth Warren of Massachusetts.

The question of the night will be: Who gets the better of the battle between Bloomberg, Sanders and Warren? And after the debate, do any candidates cast themselves as providing the only chance for the party to unite?

We’ve seen the likely battle lines already. After a tape emerged showing Bloomberg saying that the elimination of redlining (which made it easier for minority borrowers to qualify for mortgages) was at the heart of the 2008 fiscal crisis, Warren surfaced a 2005 video of herself cautioning that growing income inequality (which was not as big an issue then) was likely going to result in an enormous growth of mortgage defaults (that is, the fiscal crisis).

That’s Warren. Sanders doesn’t need a briefing book to know how to fit an attack on Bloomberg into his well-articulated stump speech about millionaires and billionaires having too much control of the U.S. political system.

The opportunity for both Sanders and Warren at the debate will be that they just need to attack Bloomberg. An effective attack may help the currently flailing Warren recapture some of the magic she had last fall, when she appeared as the Democratic front-runner and liberal darling of the party. She’s since basically been eclipsed (again) by Sanders.

With Warren flailing, Sanders essentially owns the left wing of the party – and it shows in the polling. In the most recent polls, Sanders is far ahead of his opponents.

With the more moderate wing of the party divided among former Vice President Joe Biden, Bloomberg, former Mayor Pete Buttigieg of South Bend, Ind., and Sen. Amy Klobuchar of Minnesota, Sanders just needs to maintain his strength (and his fairly high favorability, even among Democratic voters who aren’t for him). He can do that by simply attacking Bloomberg.

Bloomberg’s challenge is vastly more complicated. First, he needs to be able to respond to the anticipated attacks from the left, while also ensuring that he’s not shunted off and painted as the conservative in the race. Conservatives don’t win the Democratic presidential nomination, but moderates and sometimes liberals do.

But unlike folks who can wave off criticism – like Presidents Ronald Reagan, Bill Clinton and Donald Trump have been able to – Bloomberg so far has shown about as much charisma as a Saltine cracker.

The one place where Bloomberg has excelled is in his ability to take the fight to Trump. Part of this stems from the massive ad campaign he’s running. Some have complained that he’s basically running a general election campaign – but I’d argue that that’s Bloomberg’s claim to the nomination.

The one thing that unites the entire Democratic Party – from the “Bernie Bros” to the “Never Trump” Republicans who are planning to vote Democratic – is a deep hatred of the current incumbent. Bloomberg’s message is that he’ll spend as much as several billion dollars making that case until November: “Mike Can Do It.”

If Bloomberg comes out of the debate unscathed by the attacks from the left – and maintains a more moderate persona focused on beating Trump – then he’ll have had a successful night. He will then be able to use his fortune to eclipse the other moderate candidates seeking the Democratic presidential nomination.

Sanders needs to make the case – without offending the more moderate parts of the Democratic Party – that only his proposed solutions have a chance to address the issues of climate change and income inequality that Democrats care about.

If the senator from Vermont can do this he will continue to maintain the support of his base, and possibly make inroads among the moderates who are beginning to think he may have an insurmountable lead.

The big question for me is whether the fight between Sanders, Warren and Bloomberg provides a slight opportunity for one of the three remaining non-billionaire moderates – Biden, Buttigieg, or Klobuchar.

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All of them – especially Biden – have been campaigning on a claim that their moderate positions can better unite the party for November. But the results of Iowa and New Hampshire – and the likely results in Nevada on Saturday – suggest the voters have not yet agreed.

I still believe that the best chance for the Democrats is a “Plain Beige” candidate who focuses the entire campaign as a referendum on Trump, and doesn’t call attention to himself or herself as much.

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Plain Beige may have a chance to make that case in an opening enabled by a Bloomberg-Warren-Sanders cage fight: A simple version of “we don’t need to choose between these two extremes.”

But in order for that to happen, Plain Beige needs to win a few primaries.

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