A Mexican like solution of no state being required to recognize SSMs consecrated in them but requiring states to recognize SSMs consecrated elsewhere is moderate heroish enough that Kennedy might sign on to it, especially if it gets a 7-2 or even an 8-1 decision to be the result. However, I won't like it one bit because of the erosion of federalism such a decision would entail. (It's also why I don't care for Windsor.) It'd be far better in my opinion to simply go ahead and use the core of the reasoning of Windsor and simply declare state recognition of SSM to be a right.) Gets the same result and avoids weakening federalism more than it already has been.
7-2, 8-1, and 9-0 are all impossible. Alito, Scalia, and Thomas are not going to sign on to SSM in any way, shape, or form, period.
