(Opinion) The question is deliberately biased. Rather, it should have been phrased:
Groups in the U.S. that harbor Anti-Semitic tendencies often target other groups. Identify religious or ethnic groups that are targeted in a similar fashion.
I can't help but wonder if there was another question with the exact same phrasing, but substituting "radical left-wing" as an identifier? (end of Opinion)
Regardless, Anti-Semites tend to be racist and sexist as well, since those feelings coexist well with each other. Anti-Semites almost always attack Christian and Islamic beliefs because of the integral similarities, and they then project their prejudice onto "different" people. In the U.S., where freedom is extended to all races, religions, and genders, Anti-Semitism is a good identifier of hidden or innate prejudices; in conversation, if it can be kept civil, these beliefs almost always surface.