As Hannity keeps saying, Trump needs a higher percentage of Republicans to back him.
GOP members who are not on-board now really aren't even soft conservatives/liberal Republicans. They're RINOs at best. Reagan won with 74% support; Trump can win with 85% or more support.
Cruz is irrelevant. He had a chance to be a perceived "kingmaker" and have a future as a power player in the establishment. His failure to endorse TRUMP prior to, or during, the convention sealed the deal for Cruz becoming irrelevant. TRUMP has done all this on his own, having a Cruz endorsement now won't sway anyone (or if it does, they're pretty brain-dead)...