The Iowa caucuses take place on Monday, so we have only a few days left before this first and most ridiculous part of the primary process comes to a close. Like Lawrence of Arabia crossing an endless desert of frozen corn, the candidates have steeled their hearts and trudged through the state's 99 counties, with no diner or living room too small to receive their desperate supplications. If you look at the polls, it's easy to get confused: Some say Hillary Clinton is ahead of Bernie Sanders, while others show the reverse. On the Republican side it's the same. Is Donald Trump leading, or Ted Cruz? There's an answer, one that bodes well for Clinton and Cruz — and shows how ridiculous Iowa can be.

Before we get to those polls, let's take a look at what goes on in Iowa. While the idea of voting as a communal act requiring you to gather with your neighbors in order to fulfill your democratic duty has a certain archaic charm, what it is most of all is a huge pain in the behind. It's a little more reasonable on the Republican side, where voters come to the caucus site, spend some time listening to local apparatchiks talk about the party's business for a while, and then are finally allowed to vote with a secret ballot. Democratic caucuses, on the other hand, are a more complex enterprise, where representatives of the candidates make speeches, then everyone arranges themselves into different corners of the room depending on which candidate they support, then the supporters of candidates who don't meet a threshold of 15 percent support in that caucus have to find a new team to join. What ensues is then a period of fevered negotiation, until everything finally gets sorted out and the votes can be tallied. It takes hours.

Naturally lots of people aren't going to go through all that. Those who avoid such activities include people with inflexible jobs (more likely to be low-income), people who are house-bound (no absentee voting allowed), and people who just don't care enough to give over a whole evening to the caucus.

That means that for all the tributes the caucus defenders make to the informed and committed Iowans who hold the country's fate in their hands, turnout in the caucuses is very low. In 2008, the last time both parties had contested primaries and the occasion of Barack Obama's extraordinary campaign, turnout rocketed all the way up to 16 percent of eligible voters. That was a major boost over the previous contest with races in both parties, in 2000, when it was 6.8 percent.

When turnout is that low, the people who do turn out are going to be an unrepresentative group; among other things, they'll be older and more likely to have caucused before. This is where the difference between the candidates' supporters comes in. As Nate Cohn of The New York Times recently noted, Iowa polls that use lists of registered voters as the universe from which they draw a sample tend to show Clinton in the lead, while polls that use random-digit dialing — surveying everyone, whether they're registered or not and independent or not (registered independents can't vote in the caucuses) — show Sanders leading. Trump's situation is probably similar — his unusual candidacy is bringing in people who are not party regulars, but that also means they're less likely to turn out.

Here's another interesting data point. A recent CNN poll asked whether respondents had participated in their party's last competitive caucus (2012 for Republicans, 2008 for Democrats). Among the whole sample of Republicans, Trump led Cruz by 11 points, but among those who caucused last time, Cruz led by 2. On the Democratic side, the effect was even more stark: Sanders led Clinton by 8 points among all respondents, but among those who caucused in 2008, Clinton led by 17.

Bernie Sanders might say, that's OK — I'm going to bring out all the young people who support me, and even if they haven't caucused before, their enthusiasm will carry them to the caucus site. Which could happen. But consider this. That youth-driven Obama campaign? In 2008, it did indeed succeed in bringing out unprecedented numbers of young voters, and those under 30 made up 22 percent of the Democratic caucus-goers. But four years before, when John Kerry won, young voters were 17 percent of the caucus-goers — a little less, but not an enormous difference. The reason the increase was only a few points was that everyone turned out in larger numbers in 2008, young and old alike.

Even though Sanders is unusually dependent on young voters, he might mount a turnout operation that would bring them to the caucuses in numbers they haven't shown before. But if Barack Obama's 2008 effort — probably the most skillful presidential campaign in American history — could only boost youth turnout in Iowa by a few points, it would be truly remarkable if Sanders could do better.

None of this is to say that the result is already determined, because it isn't. Things can change fast in an election. But just imagine what it would be like if voting wasn't such a hassle, and everyone could do it quickly and easily. Then the campaigns wouldn't spend all their time trying to cajole people to the polls, and they could concentrate on persuading the voters that they're actually offering good candidates. Who knows what that would produce.