The nationwide survey, which is based on telephone interviews with more than 35,000 adults from May 8 to Aug. 13, 2007, is the second installment of a broad assessment Pew has undertaken of trends and characteristics of the country’s religious life. The first part of the report, published in February, depicted a fluid and diverse national religious life marked by people moving among denominations and faiths.

According to that report, more than a quarter of adult Americans have left the faith of their childhood to join another religion or no religion. The survey indicated that the group that had the greatest net gain was the unaffiliated, accounting for 16 percent of American adults.

The new report sheds light on the beliefs of the unaffiliated. Like the overwhelming majority of Americans, 70 percent of the unaffiliated said they believed in God, including one of every five people who identified themselves as atheist and more than half of those who identified as agnostic.

“What does atheist mean? It may mean they don’t believe in God, or it could be that they are hostile to organized religion,” Mr. Green said. “A lot of these unaffiliated people, by some measures, are fairly religious, and then there are those who are affiliated with a religion but don’t believe in God and identify instead with history or holidays or communities.”

The most significant contradictory belief the survey reveals has to do with salvation. Previous surveys have shown that Americans think a majority of their countrymen and women will go to heaven, and that the circle is wide, embracing minorities like Jews, Muslims and atheists. But the Pew survey goes further, showing that such views are held by those within major branches of Christianity and minority faiths, too.

Scholars said such tolerance could stem in part from the greater diversity of American society: that there are more people of minority faiths or no faith and that “it is hard to hold a strongly sectarian view when you work together and your kids play soccer together,” Mr. Lindsay said.

But such a view of salvation may also grow out of doctrinal ignorance, scholars said.

“It could be that people are not very well educated and they are not expressing mature theological points of view,” said Todd Johnson, director of the Center for the Study of Global Christianity at Gordon-Conwell Theological Seminary. “It could also be a form of bland secularism. The real challenge to religious leaders is not to become more entrenched in their views, but to navigate the idea of what their religion is all about and how it relates to others.”