When Cruz dropped out, there was no more hope for a contested convention and that ended Kasich’s long, long shot hopes. And it probably ended his financial backing.
Exactly.
The free food is over.
Simplest explanation.
I think that clearing the decks for Trump allows the NeverTrump wing of the GOP time to get a third party ticket ready to go in case Trump makes any serious errors between now and the end of the month.
If Trump is the lone choice, it’s easier to justify a third party latecomer than it is to try and drag Kasich and Cruz to the convention in good enough shape to topple Trump on a second or third ballot.