This could well be the first election since 2000 with an independent candidate. That has happened only four times in the past century, the others being 1912, 1948 and 2000.
And a three-way -- or even a four-way race --would be a wild card. It could take any of several forms, with different partisan winners and losers. Consider:
Suppose Donald Trump is the Republican nominee and Hillary Clinton is the Democrat. Establishment Republicans will be convinced that their party has been hijacked by a bizarre rabble-rouser; GOP elites will be unsure which is worse -- the prospect of Trump losing, or Trump winning.
Result: pressure builds for a "real" Republican to run as an independent -- a conservative but not a rightwing populist. That could be, say, Paul Ryan, or John Kasich, or Mitt Romney again.
Advantage: Democrats. The analogy is to 1912, when two Republicans ran -- incumbent president William Howard Taft and former president Teddy Roosevelt as a Bull Moose progressive Republican -- and Democrat Woodrow Wilson won without a popular majority.
Sort of the same thing happened in 1992 when independent H. Ross Perot took more votes from the Republicans than from the Democrats, and Bill Clinton became president with just 43 percent of the popular vote.
Or suppose Ted Cruz or Marco Rubio edges out Trump, who places first in delegates but doesn't quite get a majority. An enraged Trump goes back on his pledge, and runs as an independent.
Again, advantage Democrats -- but not without some complications. With Hillary Clinton as the Democrat and Cruz or Rubio as the Republican, a good number of working-class Democrats could vote for Trump and make it a close race. Still, the result is a fractured Republican Party.
But the permutations do not stop there. Suppose Sanders beats Clinton in Iowa and New Hampshire, and the chemistry of the whole race changes. It's desperation time for Clinton, when she is not at her best.
Sanders will likely lose most of the southern primaries to Clinton, but the early calendar also includes Nevada, Colorado, Minnesota and Massachusetts, all states that Sanders could win. And then there are the big, liberal states of California and New York. Momentum: Sanders. He could actually be nominated.
And if Sanders is the Democratic nominee, Wall Street will just go nuts. Unlike Hillary Clinton, Sanders could spoil their con game.
There will be pressure for the sort of independent candidate for whom economic elites have long been clamoring. Someone who is liberal on social issues but center-right on fiscal issues and economics.
That would be Michael Bloomberg, who has been hankering to run and who could easily finance the race out of his own billions. This, of course, would be a catastrophe for Democrats--the flip side of Republicans splitting down the middle.
The last time the Dems were split was when Ralph Nader ran as an independent in 2000. And we know what happened. Bush didn't win the election but he won the Supreme Court.
And -- hold onto your hats -- it doesn't end there. What if the Republicans nominate Trump and the Democrats nominate Sanders? We could even have a four-way.
The GOP could haul out somebody like Romney and Wall Street Dems could turn to Bloomberg. The result would be anybody's guess.
In theory, the financial elite might go into a coke-filled room (or maybe a Koch-filled room) and try to agree on a single moderate candidate. The problem, however, is that even mainstream Republicans are now far to the right on social issues. It's hard to think of anyone who would pass muster with both Republican and Democratic billionaires.
We've had a four-way once in the past century. That was in 1948, when the Dems split three ways. The progressives nominated former Vice President Henry Wallace. The Dixiecrats broke away and nominated Sen. Strom Thurmond. Republican Thomas Dewey was certain to win, but the people liked Harry Truman's feistiness and Truman pulled it out.
The takeaway: the 2016 election has been pretty weird so far--and is likely just to get weirder. If only this were an HBO series instead of our cherished country.
Robert Kuttner is co-editor of The American Prospect and professor at Brandeis University's Heller School. His latest book is Debtors' Prison: The Politics of Austerity Versus Possibility.
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