I will use this page as reference for what is considered a swing state so there is no confusion.
http://en.wikipedia.org/wiki/Swing_stateI will count Florida, but not Michigan, seeing as how Obama's name wasn't on the ballot in MI. I am willing to concede the point that Florida should be removed from Hillary's column, but I still think she wins the state anyways regardless of whether Obama campaigned in the state or not.
Let's go through the irrelevant states that each candidate has won for various reasons - they are either traditionally Democratic states that will vote Democratic, or traditional Republican states that will vote red regardless of who is nominated.
Republicans - Alabama, Alaska, Arizona, Georgia, Idaho, Indiana, Kansas, Kentucky, Louisiana, Mississippi, Montana, Nebraska, North Carolina, North Dakota, Oklahoma, South Carolina, South Dakota, Tennessee, Texas, Utah, West Virginia, Wyoming
Democrats - California, Connecticut, Delaware, D.C., Hawaii, Illinois, Maine, Maryland, Massachusetts, New Jersey, New York, Rhode Island, Vermont
Now I will list the swing states each candidate has won and how many electoral votes they have total when you add all of them up.
Obama Washington - 11
Colorado - 9
Minnesota - 10
Iowa - 7
Missouri - 11
Wisconsin - 10
Virginia - 13
Total for Obama: 71
HillaryNew Hampshire - 4
Florida - 27
Ohio - 20
Nevada - 5
New Mexico - 5
Arkansas - 6
Total for Hillary: 67
Swing states yet to have votedPennsylvania: 21
Oregon: 7
Obama holds the slight lead over Hillary among swing state electoral votes. However, Pennsylvania has 21 electoral votes and they vote 7 weeks from now. Whomever wins Pennsylvania will have more electorate voters from potential swing states. I am convinced that whomever wins Pennsylvania should be the frontrunner for the nomination. That is really the only way to decide this. Both sides are claiming that each side specific strengths among swing states, and they are right.
Hillary has the lead in the traditional swing states like Ohio and Florida that have decided the election the past few years, but some of my fellow Obama supporters have told me that Obama could win through the "backdoor" so to speak, winning other swing states like Colorado that Hillary doesn't have quite the appeal in. Others argue that Obama could win Ohio and Florida in the general. It's all up in the air and up to interpretation.
I still say: Let the winner of Pennsylvania decide whom should be the frontrunner for the nomination. Pennsylvania is the most important state that we need to keep blue.