Don't think it was blind luck that Obama swept all the swing states except for NC & IN in 2012. While clearly not as strong as Obama's team, Mitt's team was much more quantitatively oriented than Trump's team will be. HRC's campaign won't be as aggressive as Obama's, so doubt they make big reaches for states like GA or UT unless they see high probability of success.
What I was saying is Obama was a quality candidate running against two other quality candidates. This is as opposed to a candidate like Trump or Cruz who are on the fringes of politics.
I think we agree that in a close election with people like Obama, McCain, Mitt or HRC data mining may provide the difference. However, it likely won't matter in November when you have one competent candidate and one wacko.