Just what this presidential campaign needs, another know-it-all billionaire. Whip out your checkbook, Michael Bloomberg, and come on in.

News that the former New York mayor is thinking about entering the race is no surprise, when you think about it. It’s well-known that he has long wanted to be president, the one impediment being that neither of our two major parties is likely to nominate him. But with Donald Trump leading on one side and Bernie Sanders running strong on the other, Bloomberg must say to himself the same thing that so many other Americans are muttering, or perhaps wailing: You’ve got to be kidding me.

Widespread reports quoting sources close to the 73-year-old Bloomberg said he is willing to spend up to $1 billion — of his estimated $37 billion fortune — to wage an independent campaign in the general election. He would only do so, however, under certain conditions that would normally be considered quite unlikely.

But likeliness, like Elvis, has left the building. So why dismiss the Bloomberg trial balloon out of hand, given all the other outlandish things that are happening?

The first element in Bloomberg’s scenario is that either Trump or Ted Cruz wins the Republican nomination. Since Trump and Cruz are running first and second in the polls, this could happen.

With less than a week to go before the Iowa caucuses, recent state polls show Trump once again in the lead. How badly does he want to win there? On Friday night, after a full day of campaigning, rather than fly home to his Manhattan penthouse or his Florida mansion, he slept at a Holiday Inn Express in Sioux Center, a small town (pop. 7,308) in the conservative northwest corner of the state. On Sunday he was in eastern Iowa, where he went to church and reportedly left $100 in the collection plate.

Trump figures that if he can sweep the first three states — Iowa, New Hampshire and South Carolina — nobody will be able to catch him. The only contender with a realistic chance of stopping the Trump blitzkrieg before it starts is the ultraconservative Cruz, who remains within striking distance in Iowa.

Either man could lead Republicans to a historic defeat in November — or not. That depends on the second element of Bloomberg’s scenario: Either Sanders wins the Democratic nomination or front-runner Hillary Clinton emerges from the primaries as a badly damaged standard-bearer.

I must report that this, too, could happen.

History doesn’t repeat itself, but sometimes it does rhyme. As Barack Obama did in 2008, Sanders is running an insurgent “movement” campaign against the Clinton machine and the Democratic Party establishment. What if Sanders were to win a narrow victory in Iowa followed by a big one in New Hampshire? What if the Clinton campaign were to respond in ways that were clumsy and counterproductive? What if Sanders’ call for a grass-roots “political revolution” turns out to be the message that inspires passion among rank-and-file Democrats?

Clinton, of course, could rally her troops and hold the line in South Carolina and on Super Tuesday. But she could be weakened by the battle. Meanwhile, the federal investigation of her State Department emails continues — and who knows where it will lead?

So there’s a chance the Republicans will nominate either a shoot-from-the-lip real-estate tycoon who has never held elective office or a first-term senator whose uncompromising views are far to the right of his party, to say nothing of the nation. And there’s a chance the Democrats will nominate either a wounded establishment figure — in a non-establishment year — or a 74-year-old self-described democratic socialist.

If you’re Bloomberg, why wouldn’t you think about jumping in?

There is one pretty good reason, actually. Even this year, it is hard to fathom how an independent candidate could actually win the presidency. In a three-way race, if no one got a majority of the electoral vote the election would be thrown into the House of Representatives — which is populated by Republicans and Democrats whose instinct will be to support their own.

And besides, long before we reached that point, my guess is that prominent presidential hopefuls from the past in both parties would hear the nation’s call, real or imagined. Are you listening, Joe Biden? What about you, Mitt Romney?

I wonder who’s booking hotel rooms for July in Cleveland and Philadelphia. This year, both party conventions might actually be interesting.

Eugene Robinson’s email address is [email protected].

© 2016, Washington Post Writers Group

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