Religion has been high on the agenda this campaign season as candidates visit churches, talk about their personal beliefs and rack up religious endorsements -- all in an effort to mobilize faith-based voters. But there's long been an uneasy relationship between religion and U.S. politics. According to a recent Pew Forum survey, nearly 70 percent of Americans agree that it is important for a president to have strong religious beliefs. And more than 60 percent say they would be less likely to support a president who doesn't believe in God. But at the same time, more than four-in-ten Americans say they get uncomfortable when politicians talk about how religious they are. Should religion matter when choosing a president?