For starters, the congressmen (McDermott, Levin?) who went to Baghdad and appeared on CNN to criticize the US just before we invaded Iraq. It sure looked like aid and comfort to me.
How about the ANSWER, MOVEON notables calling for the assassination of President Bush?
I know that a new HUAC will never happen, yet the bulk of the leadership of the democrat party wouldn't mind our defeat in the war on terror if it meant their return to power.