We are updating this post now that voters in Utah are preparing to head to their caucus sites on Tuesday night.

Donald Trump is getting crushed in Utah.

First, the state's adopted son, Mitt Romney, went gunning for Trump for weeks on end, and eventually revealed that he was backing Ted Cruz in the upcoming caucuses. Utah is adjacent to Idaho and Wyoming, where Trump has seen two of his biggest losses so far, both to Cruz. In a poll from Y2 Analytics released over the weekend, Trump comes in third, 42 points behind Cruz. (If Cruz wins more than half of the votes in the state, he gets all of the state's 40 delegates.)

What's even more remarkable, though, is that another poll suggested that Trump would lose to either Democrat in Utah in the general election. Utah is, of course, one of the reddest states — if not the reddest state — in the country. "Any matchup in which Democrats are competitive in the state of Utah is shocking," Brigham Young University's Christopher Karpowitz said to the Deseret News about that result.

But why? Why is Utah — which is also adjacent to Nevada, which Trump won, and Arizona, where he leads — so hostile to Donald Trump?

One answer seems to be that the state is so heavily Mormon. Our Katie Zezima looked at the overlap of Trump opposition and the Mormon population, which can be illustrated fairly simply. Where there are more Mormons in Idaho and Nevada, Trump has done worse.

That correlation holds loosely for the rest of the country, too. In places where there is a higher density of Mormons, as measured by the Association of Statisticians of American Religious Bodies, Trump tends to do worse. Much worse.

But what's interesting is that this may not actually be about Mormonism at all.

That Deseret News poll, for example, found that Utah's Mormons had about the same level of support for Trump as the state's non-Mormons. The real divide was between those who attend church regularly and those who don't.

As Gallup found in February, no one attends church services more regularly than residents of Utah. Fifty-one percent of the state's residents indicated that they go to church weekly.

In 2014, a Pew Research survey determined that Mormons were the most likely religious group to attend services regularly, far more than other faiths.

That survey also found that 85 percent of Mormons pray daily, compared with 59 percent of Catholics and 79 percent of evangelicals.

Daily prayer and regular church attendance are two of the components of the Barna Group's definition of a "practicing Christian." Barna, a California-based research firm, conducts regular surveys of the religious lives of Americans. In February, it looked at how different groups viewed the Republican contenders. No group had a more negative view of Donald Trump than "practicing" Christians.

What may be prompting the stiff resistance to Trump, then, isn't just that Utah is home to a lot of Mormons -- it's that those Mormons are more religious and that religious voters are more likely to view Trump with hostility.

The good news for Trump is that most of the states with the largest groups of regular churchgoers have already voted. Most are in the Bible Belt, as you might expect -- a region where Trump did very well. Political beliefs are more complicated than they might appear at first glance. Sort of like religious ones.