How? He's unknown outside Ohio, he's already ran for shit in not one but two bordering states (3rd in Michigan, 4th in Kentucky, and not carrying a single county in either one), and he has no money. He won't break 10% anywhere up East.
Perhaps, but I was surprised when he came very close to beating Trump in Vermont on Super Tuesday. I’m pretty sure Kasich received 30% of the vote there in a five man race. Considering his strong second place finish in NH too, I wouldn’t be so sure he won’t do well enough in the Northeast to take some delegates away from Trump, even if he doesn’t win any states outright. (And, not that it matters, but Kasich won the counties where Ann Arbor and Kalamazoo are located in Michigan.)