NEWT GINGRICH has had a rough week:  Democrats said he was racist for calling Obama a "food stamp president" . . . Republicans are mad at him for going after Congressman Paul Ryan's Medicare plan . . . and now he's been GLITTER-BOMBED.

During a book signing in Minneapolis on Tuesday, a gay activist named Robert Erickson dumped a box of glitter on Newt and his wife Callista, and yelled, quote, "Feel the rainbow, Newt!  Stop the hate!  Stop anti-gay politics!"

He was immediately taken away by security, yelling, "It's dividing our country and it's not fixing our economy.  Do it like a man."  (???)