From CBS News: 

In 1972, fewer than 3% of Americans identified as nondenominational Christians. Now it’s 14%, or nearly 40 million people, according to the General Social Survey.

Burge believes it’s possible nondenominational Christians could overtake Roman Catholics in the next 15 years to be “the largest religious tradition in America.”

“I think it’s, we’re moving away from authority structure,” [Professor Ryan] Burge said.

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