This is way beyond priceless, seriously.   Even entrenched die-hard democrats will admit this regular speak and delivery is funny.  Often good natured humor can be used as a weapon (Ronald Reagan was the absolute master of that), and in this instance Trump hits it right out of the ballpark.  Funny stuff:

This approach will do more damage to Hillary Clinton -as a presidential candidate- than a thousand congressional investigations. Candidate Trump knows that too.
Trump frames the discussion in such a manner that it creates a situation where Clinton allies don’t want to try and defend the indefensible. No one likes being laughed at.