Leaders of the institutions that sponsored the survey offered it as a counterargument to the currents of Islamophobia that they say have tainted much political and personal discourse during the past 10 years.
The report, they said, shows a strong willingness on the part of mosque leaders to encourage worshippers to engage in U.S. society, including its politics.
"Post-9/11, I was really afraid of the new negative attitude Muslims were receiving," said Safaa Zarzour, secretary general of the Islamic Society of North America. "It made me feel that Muslim communities would feel marginalized from American society, and that to me is where things can become dangerous."
But that did not happen, he continued.
"We see outreach and engagement among mosques mosques with food pantries, medical clinics. You have people who can look at mosques in their neighborhood and see Muslims as people who can help, not people to be feared."
The survey, "The American Mosque 2011," counted 2,106 mosques in the nation, and a spike in the number of people who attend Eid prayers, the Muslim holy days that tend to attract more people than any other. In 2011, the survey found 2.6 million people had gone to Eid prayers, up from 2 million in 2000.
That last figure challenges many previous estimates of the U.S. Muslim population, which generally fall well below 3 million. Given the number of Muslims who do not pray the Eid prayers, the total number of U.S. Muslims likely exceeds 3 million, perhaps by more than a million, the study's authors conclude.
Within those mosques, a more flexible attitude toward the interpretation of Islam is more typical, with 56 percent of mosque leaders describing their own approach as one that sees the Quran and other Muslim holy writings as a guide relevant to modern life.
Of the remaining mosque leaders surveyed, 31 percent take a more conservative approach and base their interpretations on centuries of Islamic scholarship. Another 11 percent follow a single, traditional religious school of thought.
Just 1 percent followed a strict interpretation that the study's authors likened to Wahhabism, the brand of Islam that predominates in Saudi Arabia.
For most of U.S. history, American Muslims have not drawn much attention. That changed on 9/11, but much of the new focus on Muslims has been negative, and depicted American mosques as a breeding ground for radicalism. The House Homeland Security Committee has held a series of widely publicized hearings on the subject.
But the 524 mosque leaders who were interviewed for the report tell a different story, according to the survey. Asked whether they agree that American Muslims should be involved in U.S. institutions, 98 percent agree or strongly agree; none strongly disagree.
And 91 percent of mosque leaders either agree or strongly agree that Muslims should participate in the U.S. political process.
Zahid Bukhari, president of the Islamic Circle of North America, suggested American politicians from presidential candidates to local office seekers should reach out to Muslims voters. "Visit a mosque," he said.
The study also reveals the diversity of American mosques. Among regular mosque participants, 33 percent are South Asian, 27 percent are Arab, and 24 percent are African-American.
The survey is part of a larger, continuing study of American congregations called Faith Communities Today, a multifaith effort.
The mosque survey in particular was sponsored by the Hartford Institute for Religion Research at Hartford Seminary; the Association of Statisticians of American Religious Bodies; the Council on American-Islamic Relations, the Islamic Society of North America, the Islamic Circle of North American and the International Institute of Islamic Thought.
• A steady conversion rate. In 2011, the average number of converts per mosque was 15.3 compared to 16.3 in 2000.
• A decrease in the number of mosques in urban areas and an increase in suburban mosques. In 2000, 16 percent of mosques were located in the suburbs, compared to 28 percent in 2011.
• A shift in geographic distribution of mosques, which in 2000 were mostly concentrated in the Northeast. In 2011, the South had the greatest number of mosques, 34 percent, compared to 26 percent in 2000.
• About 7 percent of the mosques surveyed identified as Shiite, with the greatest proportion located in the West (37 percent).