McCarthy's paternal grandmother was German. The other three grandparents were all Irish.
I don't doubt that many anti-Semites at the time supported McCarthy (though a famous survey at the time contradicted this), but no way was he an anti-Semite, despite what the liberals claim. To the liberals being anti-Communist is a crime in and of itself.
I helped edit a book on Minnesota politics years ago, and ran across some info on Joe McCarthy. He was no anti-Semite, and neither were the bulk of the Midwest’s German-Americans.