“Nearly impossible” is not “impossible”.
The Republican establishment has EARNED the title of “Stupid Party” for very good reason. In regards to The Donald, they seem to have a death wish, preferring to shed themselves of The Donald, rather than risk the possibility that he could turn this into a landslide for himself and other like-minded Republican incumbents and challengers of what are currently Democrat seats, or those open seats that now dot the landscape in both the House and Senate.
The threat goes on, that if The Donald does not reach the 1,237 delegate votes on the first ballot, the convention will not merely be contested, it will be thrown wide open. And even if the threshold of 1.237 delegates is met and exceeded, the credentials of those delegates will be challenged, and an attempt will be made to snatch the nomination away.
All I may suggest is, that if you are going to attempt to take out the king, you better to hell not miss. Retribution is an ugly thing.
Trump gets some 1300 delegates total. A week ago, I had him at just 1240 to 1250. After Tuesday, that changed.