CBS's list of battleground states in 2016:
Georgia - 5.1%
Virginia - 5.3%
North Carolina - 3.7%
Ohio - 8.1%
New Hampshire - 0.3%
Pennsylvania - 0.7%
Florida - 1.2%
Arizona - 3.6%
Colorado - 4.9%
Wisconsin - 0.8%
Michigan - 0.2% (went from the bottom of the close state list in 2012 to the top in 2016)
Iowa - 9.4%
Nevada - 2.4%
Minnesota isn't even on there... It was a 1.5% state, Maine was a 3% state.
Also, news networks prematurely called Pennsylvania for Barack Obama in 2012. If they didn't, Romney probably would've won it. (sure, by about the same margin as in North Carolina)
NBC's staff said "they need to win Pennsylvania, the election is over if the Democrats lose Pennsylvania." If Obama lost Pennsylvania, he still would've won (312 to 226).
This was more theoretical than mathematical. PA had consistently been polling a couple points to the left of the nation prior to the election, so a Romney win in PA would have indicated that he was winning the NPV by 3-4 points.