From the American Enterprise Institute…

In 2011, for the first time since the question was first asked in 1958, a majority of Americans (54%) told Gallup they would vote for a generally well-qualified atheist for president; 43% said they would not. Still, the proportion of Americans willing to vote for an atheist is lower than for the other groups Gallup examined:

•    Black:                    96%
•    Woman:                95%
•    Catholic:                94%
•    Hispanic:                92%
•    Jewish:                  91%
•    Mormon:                80%
•    Gay or lesbian:       68%
•    Muslim:                  58%