Conversation so far:
What support Joseph McCarthy provide for Roman Catholics?
One of the strongest bases of anti-Communist sentiment in the United States was the Catholic community, which constituted over 20% of the national vote.
What was his involvement with that group?
McCarthy identified himself as Catholic, and although the great majority of Catholics were Democrats, as his fame as a leading anti-Communist grew.

Question: What cooperation he had with them?
Self-contained rewrite: What cooperation Joseph McCarthy had with Roman Catholics and the Kennedy Family?