And Fox promptly cancels the debate.
ADDED: The poll is defective because after Trump got out, Kasich got out, and then Fox canceled. The article kind of buried that key fact, and I didn't dig it out. Sorry. But I want to say that Kasich's withdrawal shows the significance of the 5th option on the poll, which is that being alone on stage with Cruz was dangerous to Kasich. As soon as the big target Trump was out, Kasich declined the opportunity. He was fine with passively looking norma while Cruz attacked Trump, but he did not want the opportunity to go one-on-one with Ted.
Meanwhile, his staying in the race stops Ted from having the advantage of going one-on-one with Trump. There's something very annoying about the Kasich candidacy. He has some big problems that are not getting much attention, and he's hanging back waiting for a process to play out that will leave him standing there looking like the rightful owner of the nomination. But he has not fought for it and there's no reason to think he'd be a strong opponent for Hillary.