You can tell the Marco Rubio insult tour against Donald Trump is working because so many talking heads are whining about how small it makes him look.
In fact, Rubio has been brilliant at this. He has thrown Trump off his game, gotten under his skin, and is living rent free in his head. To have television commentators talk about how Trump insults everybody and gets earned media because of it, then complain when Rubio does the same is not serious analysis, but Trump partisans making an admission against interest.
Marco Rubio needs to keep this up this line of attack on Trump and keep Trump off his game.