If you're a churchgoing Christian, the polls are probably baffling.

They say Christians favor Donald Trump for president — a man who has mocked a disabled reporter, insulted women, and repeatedly cursed in public. The polls say most Christians have a favorable opinion of him.

But if you've asked around your congregation, you probably found that Trump isn't the popular choice — and that a lot of people really don't like him.

So what's happening?

As it turns out, there's a big difference between people who identify as Christians and people who go to church regularly.

The Barna Group, an evangelical firm that conducts some of the best religion polling in America, put out a poll last month that looked at the primaries from the context of voters' religious beliefs and practices.

The first finding: Christian Republicans generally like Trump. About 32 percent said they would vote for Trump in the primary, which is 13 percentage points ahead of the next candidate, Ted Cruz.

The second finding: If you take the subset of that group who has been to church in the past week, Ted Cruz earns about 30 percent of the vote, versus Trump's 24. And more than a third have an unfavorable opinion of Trump.

Many church leaders are baffled by why Christians like Trump, but this might be a hint

An unusual number of church leaders have come out against Trump — perhaps most prominently Max Lucado, a well-known pastor and author who wrote in the Washington Post:

Such insensitivities wouldn’t be acceptable even for a middle school student body election. But for the Oval Office? And to do so while brandishing a Bible and boasting of his Christian faith? … But the concern of this article is not policy but tone and decorum. … "For out of the overflow of the heart the mouth speaks," Jesus said. Words are a heart monitor. Christians would do well to summon any Christian leader to a higher heart standard. This includes pastors (especially this one), teachers, coaches and, by all means, presidential candidates.

Tony Beam, a pastor who hosts a radio show called Christian Worldview Today in South Carolina, went on air after the first Republican debate, during which Trump attacked the way women looked. Beam told This American Life:

I come and crack the microphone after that first debate. And I'm like, [giggling] Trump's done. This is it. He's really stepped in it now. And I'm plastered with people calling me telling me how glad they are the way Trump handled himself and that he won that debate. And I was stunned. I thought I was doing somebody else's talk show, that they had switched frequencies on me and not told me, and that I was actually doing a show from a different location. This is crazy. This is not who we are.

In past years, Christians — in particular, evangelical and born-again Christians — have favored a candidate other than the frontrunner early in the election cycle, before coalescing around the eventual nominee.

In 2008, this group heavily favored Mike Huckabee, who was significantly more popular among evangelicals and born-agains early in the GOP primaries. In 2012, that candidate was Rick Santorum and, later, Newt Gingrich. But eventually they came around to John McCain and Mitt Romney.

This election, it looked as if that candidate would be Ted Cruz. But by the New Hampshire primary, evangelicals and born-again Christians already favored Trump, and he's only widened his lead in Nevada and South Carolina.

In short, Trump is very popular among self-identified Christians.

Meanwhile, the group that's left behind is active Christians who say they've been to church in the past week. Their support of Ben Carson and Ted Cruz hasn't made a meaningful dent in Trump's popularity.

The number of churchgoing Christians is falling rapidly. This really does matter.

One reason churchgoing Christians don't have as much as a sway on this election might be that there just aren't as many of them.

From 2007 to 2012, there was a 5 percentage point drop in the number of people who said they were Christian, according to a Pew Research study. The number went from 78 percent of Americans to 73 in just five years.

But it's not just that fewer people are identifying as Christian; it's that even the people who still identify as such are going to church less frequently — and as we see in the Trump polling, this matters.

Another Pew study shows that church attendance is falling, slowly but surely. It's a phenomenon that church leaders are aware of, and they have many theories about why this is happening. One theory is that "cultural" Christians — people who attend for reasons other than faith or spirituality — are no longer going to church with the same frequency. And a Pew study finds that Christians who seldom or never attend church are rapidly identifying as religiously unaffiliated, as opposed to Christian.

Pope Francis said Donald Trump is "not Christian"