Scandalized by a left-wing presidential candidate running on the idea that rich people have too much influence in politics, a billionaire oligarch has decided he shall personally purchase the presidency. Ladies and gentlemen, I give you Michael Bloomberg.

The announcement came over the weekend, and according to reporting in The New York Times, it was largely prompted by the fact that Bernie Sanders has come within striking distance of Hillary Clinton in the polls. Bloomberg is said to be frustrated and alarmed by Clinton's mild steps to the left in the primary, even as she attacks Sanders from the right, casting him as a tax-and-spend liberal. (It's a good window into the ideology of very rich social liberals.)

Bloomberg says he's willing to spend a billion dollars of his own money to mount a third-party challenge, which poses the very real possibility of splitting the Democratic vote and throwing the election to Donald Trump. This sparked furious anger among left-wingers, for obvious reasons. Yet the most immediate political danger is to Hillary Clinton.

But first, why would Bloomberg bother? It's impossible to exaggerate the titanic self-regard of the modern plutocrat. It's just possible that he actually believes he could win — perhaps egged on by the usual coterie of worshipful hangers-on anticipating skimming off a piece of that billion dollars for themselves. However, given how much money he had to spend to pull off quite a narrow victory over a Working Families Party challenger in the race for the mayoralty of New York City, he likely understands quite well that he can act only as a spoiler.

At any rate, the potential political effect of a Bloomberg race ought to be fairly straightforward. Given the ongoing war over "New York values" in the GOP primary, it's hard to imagine many Republicans voting for a pro-choice, pro-gun control, soda-banning climate hawk. Hence, Bloomberg would peel off high-class social liberals who hate welfare and taxes but are too dim to understand that they might thereby hand the presidency to Trump — the only question is how many.

Some professional Democrats see this as an opportunity for Clinton. Neera Tanden, head of the Center for American Progress (the most influential center-left think tank), argued that because Bloomberg might throw the election to Trump, Sanders supporters should wise up and throw their lot in with Clinton:

This argument is very unlikely to work. First, let's be clear about what this is: a threat. Bloomberg is saying that he will allow the ordinary democratic process to proceed only insofar as it does not produce a major party candidate he strongly disagrees with, in which case he will bring his vast wealth and power (recently unfettered by Citizens United) to bear on the political system. And while he could never, ever win, he really might throw the election to Trump.

However, the initial political ramifications actually work to Sanders' advantage. Indeed, it would also be hard to imagine a better confirmation of his basic political viewpoint. The ongoing wonky debate about which candidate has the better financial reform plan is rather undermined by a ham-handed intervention from a literal Wall Street billionaire in favor of Hillary Clinton (who has personally known Bloomberg for years).

More fundamentally, Sanders' support — heavily weighted towards young people of both genders — quite obviously comes from genuine enthusiasm and commitment, not a bloodless lesser-of-two-evils tactical calculation of the kind Tanden illustrated above. People who fervently support a candidate because he validates a perception that the rich own American politics are not likely to react well to one of the richest people on the planet trying to coerce them into supporting someone else. Their commitment will very likely be strengthened — right in time for the Iowa caucuses to boot.

Therefore, if I were Clinton or another Democratic Party bigwig, I'd be doing all I could to talk Bloomberg out of running or threatening to run. He just might lose her the primary.