I think It will be Michigan Ohio Pensilvania, and possibly florida.
Whoever wins 3 out of those States will win for sure.
I think Trump will win those states because he opposes the disastrous job killing trade deals like Nafta, Transpacific Partnership, Permanent Trade relations with China as Michael moore points out here
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I saw a textual version of Michael Moore's thoughts.
He makes a compelling argument - The interesting thing for me is say it gets near election and Donald Trump is close or ahead of Hillary in opinion polls, how do the weak anti trump voters (Mightn't turn out) - Will the prospect of him winning encourage to turn out - Trump's 40% will turn out regardless of polls - Clinton probably has a solid 35% and quite shaky 36 to 45% turnout that she needs to win election.0