lol since when did Kasich become the millennial candidate
Anecdotally, I know a lot of young Republicans who are turned off by Trump and Cruz.
Trump is running a right-wing populist platform akin to a pensioners party with open white resentment. Even among my most culturally conservative Obama-hating friends, they've been raised in a racially and culturally diverse society with friends from all over the world, different cultures, different languages, relgions, etc.
Trump's campaign is just pretty horrifying to most Millenials, whether they be Democrat or Republican. Cruz is your usual evangelical doom-and-gloom candidate, and that also falls flat with a more secular younger generation. Trump and Cruz offer young Republicans nothing.
By process of elimination, that leaves John "Your Republican Dad" Kasich.