Dating back to the 1988 election, Nate Silver's state-by-state polls have been
96% accurate. Only 3 of 79 ultimately had the wrong winner:
2004 Ohio: Kerry +0.2 (Bush prevailed 2.1)
2004 Wisconsin: Bush +1.0 (Kerry prevailed 0.4)
1996 Colorado: Clinton +3.8 (Dole prevailed 1.4)