I hope he voted for Obama in Massachusetts. Where you vote is one of the residence factors. Drivers license would be another. The irony if the Kopechne Killer never got around to changing that to Florida would be so delicious.
I think you are overlooking the blatantly obvious point.
Logically, there is no possible way for you to be a sitting US Senator in one state and have your “official” residence in another.
And to try that indicates what kind of crook you are. In Kennedy’s case, it also makes him a hypocrite of the 1st order. He is one of the biggest proponents of higher taxes and more government.