According to the census of 2010 about
.8% of the American population is Muslim and 1.7 % is Jewish.
Keep in mind those Muslim figures also include the “Nation of Islam” the black racist Muslim group which has been around a long time whose theology is rejected by Orthodox Muslims.
With respect to Judaism, there are religious Jews, secular Jews, etc which makes that figure difficult to interpret.
As a college student, I worked for the U.S. Census: much goes unreported.
Of all categories, I would expect that a connection to Islam is especially unreported.