Do we have a new crisis in the US political system: individual, idiosyncratic multi-billionaires disrupting the normal workings of presidential nomination politics?

The presidential nomination system, as it developed in the modern era, is an elimination derby: it depends on losers dropping out fairly early in the process, until at most only one or two candidates remain to win the overwhelming bulk of the delegates. That’s important, because if multiple candidates accumulate delegates, then no one will wrap up the nomination – and modern conventions are not really equipped to make that choice without risking major disasters for the party.

So what’s the problem? Normally, money is a key factor in winnowing out candidates. If things start going badly, a vicious cycle quickly begins in which the candidate raises less money, and therefore the press and party actors stop taking him seriously, which makes it even harder to raise money, which generates more bad stories, and eventually there’s just nothing to do but drop out.

What it all depends on is that most campaign donations are sensitive to the candidate’s chance of winning the nomination. That’s true for most money that comes from the party network, whether in small grass-roots donations or in big chunks; it’s also true for interest group money, since interest groups rarely want to waste money on a sure loser.

But those are only tendencies. What’s dangerous about the new system, with its reliance on Super PACs that in turn may depend on only a single very large donor, is that tendencies don’t always hold in individual cases, and the right very wealthy individual going against that tendency can really make a mess. Thus the story of Sheldon Adelson, who pumped enough money into the Newt Gingrich campaign to keep him afloat after his December meltdown, and is nowthreatening to do the same even though Gingrich’s chances of being anything more than a spoiler are long gone.

It’s not that big money per se is a problem – I like well-funded campaigns! Nor is the problem one of corruption. As far as I can tell, all Adelson wants is something that Newt, and every other Republican candidate except for Ron Paul, is eager to deliver. Assuming no secret agenda, I see no corruption problem there. No, the problem is just that he may be able to keep a dying campaign afloat just because he wants to, and that may do all sorts of disruptive things to the contest.

I would say one thing, however speculative. Political scientist Jennifer Steen has found that self-funded candidates, who have been a major loophole in the campaign finance system since the 1970s, turn out to be not too much of a problem because a donated dollar buys more votes than a self-funded dollar. Now, that’s self-funding in Congressional campaigns, not outside funding in presidential races – but it’s possible that we’ll find that vanity Super PACs have a similar problem. The basic idea is that a candidate who has nothing else going for her won’t thrive just from money alone; donations help a candidate not just because they put an ad on TV, but because they indicate that she has strong support even before those ads air. By that logic, it’s possible – and again, I’m just speculating – that vanity Super PACs will have the same problem.

The parties had better hope so. Because in a very large nation with lots of rich people, it’s easy to imagine that next time around every candidate will come supplied with her own constantly refilled source of easy campaign money. And if that money can keep candidates alive from January in Iowa until the last primaries in June, then the system is going to have one massive break down.