The below figures are derived from a massive Gallup Poll conducted between January 2nd and November 30th of this year of 326,721 adults (18 and older) chosen randomly from across the nation. The huge number of respondents gives the poll a very high degree of accuracy, with a margin of error of only 1 point.
Very religious: 40%
Moderately religious: 29%
January 2 - November 30, 2012
Based on self-reported importance of religion and religious service attendance. GALLUP
While the poll shows that 69% of the American population is either moderately or very religious, the really shocking statistic is the third one -- that 31% of the population is not religious at all. That is a very high number -- even higher than the results from a recent Pew Research Center Poll, which found the number of the nonreligious to be about 20% (although growing faster than any other religious group). That means at least 3 out of every 10 people in the U.S. is either an atheist, agnostic, or otherwise has no religion.
Now the only thing this proves is that the United States is becoming less and less religious as time passes. But amazingly, the author of a new book (God Is Alive And Well: The Future Of Religion In America) takes these figures (and others dating back to polls as old as 2008) to reach the conclusion that religion is on the verge of making a big comeback in this country.