DES MOINES, Iowa -- Rumors are flying that Joe Biden and Bill Richardson have -- each -- cut separate deals with Barack Obama to throw their supporters his way if they don't hit the magic 15 percent threshold to remain viable in tonight's caucuses.

Those rumors, though, may not be true. The Richardson campaign and the Biden campaign each strongly denied reports of a deal this morning. "There is no deal," said Richardson spokesman Tom Reynolds. "We will be viable in nearly every precinct so this issue is moot." Biden aides were just as confident. "We have no deals or arrangements," spokesman Mark Paustenbach said. "We are strong enough on our own."

Of course, both long-shot campaigns have good reasons to deny any back-channel agreements -- each one has been claiming more momentum than the other, hoping for a fourth-place finish that would let them carry on through the next couple of states, at least. Publicly making contingency plans for a disappointing total would undermine that message.

Still, let's assume there really haven't been any deals cut this morning. (Early this afternoon, an Obama advisor also denied the rumors.) Despite the bravado coming from Richardson and Biden, there will be precincts where neither one has enough support for their groups of caucus-goers to remain viable. Where their voters wind up going in the next round could swing whole blocks of delegates among the top three candidates. But that's a question that is just about impossible to answer, even from the 15th floor of the Des Moines Marriott, with its panoramic views of the current center of the political world.

Strategically, both Biden and Richardson have been making arguments that sound a lot like what Hillary Clinton is telling Iowa Democrats: I've got the foreign policy experience the country needs to deal with a world of threats. A win for Obama -- which would be a setback for Clinton -- could help give someone else a chance to be the experienced candidate. But Richardson has been so friendly to Clinton in debates that many people think he's angling for a spot in her administration. So in the long run, if Richardson doesn't win the nomination, he's probably better off if Clinton does. As for Biden, the rumors run counter to his entire strategy -- beat Richardson here for fourth place, knock off John Edwards as the third candidate behind Clinton and Obama and avoid antagonizing the front-runners enough to draw fire.

The problem with all this speculation is that it's just that. Even if the campaigns involved had cut deals, there's no way to enforce them when their supporters show up at caucuses tonight. Without knowing why a voter supported Biden or Richardson in the first place, it's impossible to know whom they'd like more among the big three. And besides, Iowans famously throw ideology out the window late in the process every four years in favor of friendships that will remain long after the candidates have left town. So in the end, last weekend's poker game in Elk Run Heights might wind up mattering more than whatever Biden campaign manager Luis Navarro whispers to Obama's David Plouffe.

Yeah, that sounds like a pretty crazy way to run an election. But as you know, we pick a president with the system we have. It's not the system you might want or wish to have at a later time.