It is pretty standard for analysts to look at OH, PA, FL and sometimes MI as the big prizes that will turn the election. What this analysis misses, however, is that there are groupings of smaller swing states that can be just as influential.
For example, by any measure, IA-WI-MN should be considered to be "swing", and its 27 EV's is just as influential as Florida.
To extend the analogy further, you could even construct a Western "swing" of OR-NV-AZ-NM. That's another 27 EV's.
Given that swing states tend to break together, this is certainly a very valid way of analyzing the election.... and highlights the importance of not just concentrating on the big East Coast States.
We will have at least 2-3 big suprises this year. Oregon, Wisconsin and possibly Minnesota.