Republicans call Trump 'nuts' behind his back and say he 'doesn't understand anything': Outgoing Dem senator

Outgoing Sen. Claire McCaskill (D-MO) told MSNBC's "Morning Joe" on Thursday that many of her Republican colleagues are not nearly as deferential to President Donald Trump in private as they are in public.

When asked on the show what words GOP senators use to describe the president in private, McCaskill didn't hesitate to say that they call him both "nuts" and "weak" when he's not around.

She also get that GOP lawmakers think that Trump "doesn't really understand government" and "doesn't care to understand anything complicated" because he has "no intellectual curiosity."

She then predicted that these Republicans would live to regret keeping silent about their concerns about Trump's total lack of fitness for the presidency.

"I believe history will judge, down the line, those members of the Republican Party who have silently looked down and think they can just wait this out -- without even speaking out about the level of lying that goes on," she said. "Think about this -- the president this morning tweeted that there's nothing wrong with paying off a porn star that you had an affair with in order to win the presidency... That's what he basically said! I mean, that's crazy!"

Watch the video below.