Here is the letter Sen. Harry Reid received after Election Day in 2010:

Reid had just won a hard-fought re-election against Sharron Angle. Trump had given $4,800 to Reid's campaign.
On Sunday, Reid's office provided the letter to BuzzFeed News after Trump had tweeted that incoming minority leader Chuck Schumer is "far smarter" than Reid.
I have always had a good relationship with Chuck Schumer. He is far smarter than Harry R and has the ability to get things done. Good news!
The Trump transition team did not immediately return a request for comment.