Kasich's entry into the race was actually pretty smart, you may recall. He entered just before the first Republican debate, leveraging the small spike in polling that resulted to carve out a place for himself on the debate stage. (In doing so, he booted Rick Perry to the undercard — and then Perry became the first guy to drop out.) That move also defined Kasich's long-term strategy: get a spot in the top-tier and then stay there, no matter what happens.
Kasich won his home state of Ohio, which is more than some candidates can say. Those winner-take-all delegates accounted for 43 percent of Kasich's total delegate haul; he is still in fourth place in the delegate chase.
Here's a little factoid about John Kasich! Outside of Ohio, Kasich won a grand total of seven counties, by our count — including Trump's home county of Manhattan. Most of the delegates he won were in states with proportional delegate allocations.
Why'd he stick around so long? There wasn't much of a reason not to. His strategy was to win the nomination through the process of elimination. For the party to not give Trump the delegates he needed to clinch the nomination and then not vote for him at the convention. Then, on the second ballot, to hope that Cruz couldn't make the cut either. And then, as the party was looking around, frustrated, there in the corner, covered with a thin layer of dust, is the governor of a swing state, ready to go.
Trump's Indiana win proved to Cruz that sticking around wasn't worth it. Twelve hours later, after sticking around longer than he needed to one more time, Kasich agreed.