Trump supporters WILL stay home."
So let's say Trump goes into the convention without 1237 delegates, but has more than the 2nd place guy. If Trump can't make deals to get over the top, then he's not the great all-powerful dealmaker that he claims to be, is he?
He doesn't deserve the nomination if he can't get a majority of delegates. And let's not forget that most of his wins so far have come in states which allow Democrats and Independents to vote in the Republican primaries. In closed contests, Cruz has actually won more than Trump. If Trump proves he can win first place among REPUBLICANS, fine. Then he'll likely get the nomination. The jury's still out.
As for Trump voters staying home. Who needs 'em? I'm not convinced they're essential. Head-to-head polls still consistently show Cruz beating Hillary. On the other hand, polls consistently show Hillary beating Trump, in large part because Republicans who DON'T support Trump will stay home. And in case you hadn't noticed, in 27 of 28 contests so far, more people voted AGAINST Trump than FOR Trump.
Will you stay home if they screw both Cruz & Trump or will you march blindly to the polls and pick Ryan?