I followed the link to the FBI report in the Stiletto post, and it did not have this information. But I bet the US Census Bureau has it. If I had to guess, I would venture that there are roughly equal numbers of Jews and Muslims in this country - about 6 million.
Lot of it depends on how you count Moslems. Louis Farrakhan's group, for example, is not ordinarily thought of as really Moslem by the Sunni and Shi'ite groups.