If any of the several States decide to appoint their electors by this system, they are empowered to do. To be sure, the Founders would be bashing their heads into their desks if they ever knew this hare-brained scheme had a ghost of a chance of being enacted.
It is a very bad idea but I doubt it is unconstitutional.
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You maybe correct. People need to read the 12th Amendment.
The states receive votes based upon US Congressional members
but I don’t see anywhere that it specifies how each state shall vote.
I believe that is left up to each state.
It will be an interesting discussion and legal process if it
gets that far along.