If Nate Silver had been doing predictions in 1980, he probably would have given Carter about the same odds of winning re-election.
I vaguely remember 1980 (I was quite young then, but I followed this stuff). I recall it being SO close one week ahead of the election.
Election day was a shock - to everyone. State after state after state began to fall into the Reagan column. After the polls closed on the East Coast, the election was over. Carter conceded before 7pm on the west coast.
I will be mildly shocked this time if Obama wins. If he wins, it will be very close. I will not be shocked at all to see Romney win in a landslide. That's just how much this feels like 1980.