The Democratic Party is hanging by a thread.

I obviously don't mean that a candidate who runs under the "Democratic" brand is doomed to fall short in his or her contest with President Trump later this year. Or that politicians who affix that label to themselves are bound to lose their House and Senate seats in November. Or that state houses are bound to flip to the Republicans when voters next go to the polls. For all I know "The Democrats" will have a banner year at the ballot box.

Yet the Democratic Party as an institution is tottering and much closer to being exposed as an empty shell than is typically realized. The party is easily as weak as the GOP was just before Trump launched his hostile takeover bid during the 2016 Republican primaries. That effort was a roaring success for the candidate, who managed to leave a husk of the party in a pile on the floor and subsequently remade it from top to bottom in his own image. A somewhat different process is unfolding among the Democrats right before our eyes, but the end result could be remarkably similar. It's long past time to begin acknowledging this and preparing ourselves for the consequences.

Recall what happened with the Republicans. Back in 2012, the institutional party's preferred choice (Mitt Romney) ended up winning the nomination. But before he prevailed, voters (in polls and then in actual primary contests) floated from one unorthodox (not to say bizarre) option to the next in a restless quest to settle on someone, anyone other than the party's favorite. First there was the Michele Bachmann boomlet. Then the Rick Perry bubble. Then the Hermann Cain surge. Then the Newt Gingrich groundswell. Then finally the Rick Santorum spike. That coincided with the Iowa caucuses, which Santorum won (along with ten subsequent contests). And through it all, Ron Paul floated between 8 and 15 percent in the polls. In the end, Romney prevailed. But the grassroots resistance to the party's preferred nominee was an ominous omen of what would happen four years later.

The primaries in 2016 were actually somewhat less unsettled. Trump took the polling lead way back in July 2015 and held it solidly for all but a handful of days in early November of that year, when Ben Carson briefly edged into the lead before falling back again. This happened despite the fact — or rather, because of the fact — that Trump (a long-time Democrat with few ties to the GOP) ran a campaign that directed a torrent of abuse at the institutional party and its preferred candidates and policies on a range of issues.

In light of what's happened since, it makes perfect sense that Carson (a devoutly religious neurosurgeon with no political experience at all) was the only candidate to threaten Trump early on — and that Ted Cruz, another candidate who took aim at the institutional party and whom many in the party despised, came closest to stopping Trump late in the primary season. A long list of candidates that the institutional party would have preferred (Jeb Bush, Marco Rubio, John Kasich, Chris Christie, Scott Walker, Bobby Jindal, Lindsey Graham, and George Pataki) went nowhere.

The Republican electorate showed that it rejected the institutional party — and Trump happened to be their clear choice for an alternative. Had the voters been more deeply divided and less willing to accept the nominee once he'd been anointed the standard-bearer — and of course if he had failed to win his contest with Hillary Clinton that November — things might have turned out differently, with the party left scrambling to find a different post-2016 alternative.

But Trump did win, and roughly 90 percent of Republican voters now embrace him. Meanwhile, on the institutional side, Trump has demanded professions of loyalty from those who remained from before the time of his successful insurgency, and he's purged those who refused to bend a knee and kiss the ring of the new emperor. Today the GOP might as well be called The Trump Party.

There are some important differences on the Democratic side four years later, as one would expect given various dissimilarities between the two parties. But what's striking is how many ominous parallels there are.

The 2020 Democratic primary season has seen a huge list of established, accomplished Democrats launch presidential campaigns, fail to catch fire, and then fold: Kamala Harris, Cory Booker, Kirsten Gillibrand, Deval Patrick, Michael Bennet, John Delaney, Julián Castro, Steve Bullock, Joe Sestak, Tim Ryan, Bill de Blasio, Seth Moulton, Jay Inslee, John Hickenlooper, Mike Gravel, and Eric Swalwell.

Who's fared better? An independent socialist who only joined the Democratic Party to run for president and who ran his own surprisingly successful insurgent campaign four years earlier targeting the party's clear choice for the nomination. A former vice president who's been the top choice of the party establishment and the polling frontrunner from the time he launched his campaign but who tanked as soon as voting began and is currently in a polling free-fall. A senator and former professor from Massachusetts who's running just a few hairs to the right of the socialist and whose support now seems to be waning. A senator from Minnesota who's a Democrat in good standing but who has struggled mightily for months to rise above the low single digits in the polls. The 38-year-old former mayor of the fourth largest city in Indiana who has risen entirely on his own charm, charisma, and rhetorical panache. (No sensible member of the institutional party would have encouraged someone so green to launch a presidential bid.) And then last but not at all least, there's the ex-Republican billionaire businessman and three-term mayor of New York City who's running a self-funded campaign that's surging in the polls despite the candidate completely bypassing the institutional party.

From the socialist on the left to the plutocrat who endorsed George W. Bush on the right, with a handful of more mainstream Democratic options struggling to gain and maintain traction in the middle, this is hardly the field of a party in firm control of its own destiny and setting its voters on fire. But the real danger to the institutional party doesn't come from a lack of consensus about which candidate will prevail. It comes from the candidate with the resources to turn the party into his own private conduit to power.

Mike Bloomberg is spending lavishly, hiring reams of Democratic consultants and political operatives, and networking closely with long-time deep-pocketed Democratic donors, persuading them to act as Bloomberg campaign surrogates and to ease up on their giving to his rivals. The result? In just three months, Bloomberg has spent well over a quarter billion dollars, mostly on TV ads in major media markets, and gone from close to zero in polls to a third-place 14 percent — even though his record on policy as well as personal behavior resembles fellow billionaire Trump far more than it does your average Democrat.

Lots of commentators, not to mention the campaigns running against the Bloomberg juggernaut, have accused the Manhattan mogul of trying to buy the presidency. But these critics may be focusing on the wrong product to be purchased. Their model is Ross Perot, who (as T.A. Frank recently pointed out) spent about $60 million of his own money (roughly $120 million in today's dollars) to win 19 percent of the vote in the general election of 1992.

Bloomberg is spending on an entirely different scale — one that dwarfs anything we've seen before — and he has vastly more to spend. In a year with a lower than average return on investment, say 8 percent, Bloomberg would expect to make about $4.8 billion on a net worth of about $60 billion — meaning that he could spend nearly $5 billion on the 2020 election without depleting his fortune by a single cent.

That doesn't mean Bloomberg is guaranteed to prevail in the primaries — something that's extremely difficult to do, especially with the proportional allocation of delegates that the Democratic Party uses. But what if thinking in those terms is thinking too small? Imagine Bloomberg is merely able to ensure that neither Bernie Sanders (the early frontrunner) nor any of the other candidates can clinch the nomination outright by the end of the primary season. That would set up a contested convention — and enable Bloomberg to deploy his resources in a way we've never seen before.

What would stop Bloomberg from, say, offering every uncommitted superdelegate and every Amy Klobuchar, Pete Buttigieg, and Joe Biden delegate $1 million each to flip to him on the second ballot? And making a cool $500 million donation to the Democratic National Committee to ensure that the process of anointing him as the nominee goes smoothly in Milwaukee? This scenario would probably cost Bloomberg between $1 billion and $1.5 billion. Add that to the probable cost of $1 billion for the primary battle, and he'd be left with about $2.5 billion to spend against Trump in the 3-4 months of the general election. Without, once again, having to tap into his capital reserves at all. (For perspective, the entire cost of the 2016 election, the Trump-Clinton presidential race, and all 535 congressional races combined was about $6.5 billion.)

Farfetched? Why? Just because it's never happened before? Sort of like a demagogic reality-show star and real-estate developer with no political experience winning the Republican nomination and then the presidency?

I'd like to submit that the only thing that will keep Bloomberg from taking this path or something like it — from using his fortune to effectively purchase the institutional Democratic Party, absorb it into Bloomberg LP, and use this hybrid corporate-political enterprise to fulfill the fervent wish of Democratic voters to defeat Trump — will be his own sense of personal restraint. There is no law or institution that can or will stand in the way of it happening.

Over the past four years, the GOP has been turned into the Trump Party. Before the 2020 cycle is over, America's other major party could well be transformed into the Bloomberg Party. And there might not be anything that anyone can do to stop it.

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