Despite the overwhelming evidence to the contrary, popular perceptions in the United States, especially among political elites, continue to believe that religious Muslims oppose American democratic traditions and values. While many studies find positive relationships between mosque attendance and civic participation among U.S. Muslims, an empirical and theoretical puzzle continues to exist. What is missing is research that examines the relationships between the multi-dimensional concept of religiosity and how this is associated with public opinion and attitudes towards the American political system among Muslim Americans. Using a unique national survey of Muslim Americans, we find a positive relationship between religious beliefs, behavior, and belonging and perceptions of compatibility with American democratic traditions. Quite simply, the most religious are the most likely to believe in political integration in the United States.