I disagree that all federally elected Democratic officials support this.
Whether they personally agree or not isn't the point. The Democratic PARTY has officially endorsed this theory, and have sent their people out to spread this theory in OFFICIAL messages. It is the official position of the party.
And we should definitely call it "Politically correct" speech, because that's what it is. They liflke to accuse the left of being politically correct, so let's turn it back on them.