This is the primary. Trump needs to get the other “teams” out of the way before he gets to the “playoffs”.
And why should he give the media more ammo against Hillary?? She is the most defeatable of the Dems!
If she drops out and Biden jumps in, the game is over. Biden is far too likeable, not to mention will get sympathy support due to his kid’s death.
Trump is not going to offend the Carson or Cruz voters if he can help it and vice versa.