Why we don't really know who is ahead in Iowa right now

(CNN) First things first: The theme song of the week is "Maude."

Poll of the week: There's no poll of the week because there's been a dearth of polling for the all-important Iowa Democratic caucuses.

What's the point: Iowa's a little more than a month away, and we don't really know who is ahead, let alone who is going to win.

Our lack of knowledge is for two reasons: a lack of polling and the polls that we do have show a close race at the top.

Over the last month, there have been only two public polls conducted and released in Iowa. Neither of them use live interviews or call cell phones, which are usually the marks of the most accurate pollsters. You have to go all the way back to early November to find a poll that meets those standards.

A lack of polling means we need to be extra cautious in examining polling averages. And this year, the polls are so tight.

An average of polls since November points to a very close race. South Bend, Indiana, Mayor Pete Buttigieg comes in at 21%. He's followed by former Vice President Joe Biden at 19% and Sens. Bernie Sanders of Vermont at 19%, Elizabeth Warren of Massachusetts at 15% and Amy Klobuchar of Minnesota at 6%. No one else is polling at 5% or above.

Such a close race would lead any analyst to say it was a tossup, even if this were the polling on the eve of caucuses. Buttigieg, Biden, Sanders or Warren would all still be conceivable winners.

Given that we're more than a month away, we really don't know who the heck is going to win Iowa. We can see this by looking at polls one to two months before the caucuses since 2000. Compare the average poll standing for each eventual winner (allocating undecideds) and what they earned in the final result. The median difference has been 9 points. Four out of eight times, the difference has topped 10 points. Keeping in mind that history, even Klobuchar is still in this race.

Importantly, most of those caucuses had more polling than this one has had. Looking at the period of one to two months before the caucuses, there were eight polls in 2016, 12 in 2012, 15 in 2008 and three in 2004. You have to go back to 2000, when only one poll was conducted, to find a cycle with less Iowa caucuses polling. That cycle had clear front-runners (Democrat Al Gore and Republican George W. Bush), which is very much unlike this year.

Because of the scarcity of polls, the chance that the polling average at this point differs from the final result is greater than usual.

So what's with the lack of polling? I can think of at least four reasons Iowa polls have been hard to come by.

• First, polls (and especially high-quality polls) are expensive and getting more so. With tight newsroom budgets, polling a single state in the primary season may not be seen as a wise investment.

• Second, the impeachment saga involving President Donald Trump makes Iowa less newsworthy for now. You can imagine a universe in which the Democratic primary was the major news story, and polling of Iowa would lead the news. We don't live in that news environment, and a national poll about Trump's impeachment may be deemed to be more important by some.

• Third, there's no competitive Republican primary. You could imagine that paying for more polling would make more sense if you could get two news stories out of it. Trump, though, is cruising to renomination.

• Four, a lot of pollsters took it on the chin in the 2016 general election. Some may find that there's little need to go into the field now, given that a lot of voters may change their minds before voting begins. They may even stay out of the field forever, given that even good pollsters have a hard time in Iowa.

For folks like me, little polling and close polling mean that patience is in order. More polling will eventually come. Moreover, people will caucus soon enough, and we'll actually know who won.