If Donny Trump retains all the states won by Mitt Romney in 2012, what four narrowest margin 2012 Democratic states would be enough for him to win the 2016 presidency?
If he doesn't win Virginia or Colorado, he can still win by taking Pennsylvania (won by 4.38%, 20 electoral votes) instead. Strictly speaking, he just needs to win two states, including California or New York, though both of these are considered safe for Clinton.
Interesting just how much the battlegrounds have shifted. All election season, Virginia and Colorado have been considered safe for Clinton (I guess we'll see though), whereas states like Michigan and Pennsylvania have been his (Trump's) focus, since the polling has been much closer there. I suppose we'll see tomorrow.