Progressivism keeps moving the goal posts, attempting to redefine what extremism is.  Abortion is extreme.  Just as extreme, if not more should, as the Nazi murders of Jews.
Obama was never a centrist. Frank Davis, Saul Alinsky, Bill Ayers, Jeremiah Wright...  you don't admire, or associate with far left radicals, racists, and domestic terrorists unless you yourself are as radical as they are.  Birds of a feather and all.