Newsworthy poll numbers from ABC News and The Washington Post, which combine 5,017 interviewees during 2017, say self-identified “evangelical or born again” white Protestants have slumped to a mere 13 percent of U.S. adults. That compares with 21 percent for “nones” who lack any religious affiliation.

“Americans With No Religion Greatly Outnumber White Evangelicals,” New York magazine’s headline proclaimed. If so, that would be political dynamite due to evangelicals’ importance for the Republican coalition and Democrats’ growing dependence on “nones.”

Now, let's be skeptical for a moment -- like journalists. 

Mysteriously, 13 percent is well below counts in other recent polls, so journos ought to dig into whose numbers are best and why.

The 21 percent for “nones” closely tracks other surveys. However, two experts would argue that the “With No Religion” claim in the hed above is misleading. They are Todd Johnson and assistant Gina Zurlo who lead the Center for the Study of Global Christianity (CSGC), at Gordon-Conwell Theological Seminary in Massachusetts. Zurlo is also a researcher with Boston University’s Institute on Culture, Religion and World Affairs.

In the 2016 academic compendium “Sociology of Atheism,” Zurlo and Johnson spent 24 pages analyzing “nones.” One main point was that in the U.S., at least, those who list no affiliation or call their religious identification “nothing in particular” often hold to beliefs or practices -- only minus membership. They include “spiritual but not religious” seekers and young free-floating evangelicals who shun institutional commitments.

The key: This article distinguishes between the unaffiliated and fully non-religious atheists and agnostics. It also explains pitfalls in overseas polling.

Johnson, Zurlo, and other CSGC colleagues are a go-to source for religious statistics that are used in standard reference works, and for interpretation of them. Their regularly updated World Christian Database, newly spiffed up this year, exploits every imaginable source for past, present and future numbers for each religious and ethnic group in 234 nations and territories, alongside ample backgrounding.