There are 769 delegates remaining in the upcoming primaries. Cruz currently has 502. 1,237 needed to win nomination.
1,237 - 502 = 735 needed to win
769 - 735 = 34 “margin”
So, of the remaining 769 delegates, Cruz needs to win 735. It is already an impossibility.
Cruz is a spoiler now. He can steal some delegates using the arcane gotcha rules in some states plus whatever he can get coming in second place in most states hoping to simply deny Trump the 1237. He then believes that the GOP will annoit him. And they may even do that as an act of self preservation because is will guarantee a hillary win. They will even feed hillary intelligence in the background to help her. This will preserve the party in their mind.
Tell that to the loyalists. All they are thinking of is saving their little cabal in DC.