The Story: A new survey finds that 69 percent of American adults are very or moderately religious, based on self-reports of the importance of religion in their daily lives and attendance at religious services.

The Background: Based on the results, the survey finds that the United States remains a largely Christian nation, although one in which an increasing percentage of adults say that they don’t have a formal religious identity.

However, Gallup predicts that religion may be set to become increasingly important to Americans:

Although it is always difficult to predict the future, certain trends in the age composition of the American public suggest that religion may become increasingly important in the years to come. This is mostly the result of the fact that the number of Americans who are 65 and older will essentially double over the next 20 years, dramatically increasing the number of older Americans. As long as these aging baby boomers become more religious as they age—-following the path of their elders—-the average religiousness in the population will go up.

The report is based on more than 320,000 interviews conducted by Gallup between January 2 and November 30, 2012. Gallup asked, “Is religion an important part of your daily life” and, “How often do you attend church, synagogue, or mosque—-at least once a week, almost every week, about once a month, seldom, or never?”

The Takeaways: Some of the more interesting findings from the survey include:

• Importance of religion increases with age. Americans are least religious at age 23 and most religious at age 80.

• Women are significantly more religious than men, at all ages and within all race and ethnic groups.

• Blacks are more religious than any other race or ethnic group in America, while Jews are the least religious. Mormons are the most religious group in America.

• Religiousness is highest in Southern states (Mississippi, Alabama, and Louisiana) and lowest in states located in the two northern corners of the country (Vermont, New Hampshire, Maine, Oregon, Washington, and Alaska).

• Upscale Americans are less religious than those with lower levels of education and income, but better-off Americans attend religious services just as often.

• Republicans are significantly more likely to say that religion is important in their daily lives and more likely to attend religious services regularly than either independents or Democrats.