Earlier quoted context omitted.
The biggest problem with it is that it's unconstitutional. States are not allowed to make agreements with each other parallel to the system. EDIT: if you can get that many states to agree to it, then you could have just done a constitutional amendment. since all you need for that is for the states to agree, and the senate to agree. Senators come from the states. So... if you can't get it passed that way, it doesn't p…
Which part of the constitution says that?
Specifically:
>No State shall, without the Consent of Congress, ... , enter into any Agreement or Compact with another State
In this case, since such a deal is changing how the president is elected, and changing the balance of power between states and the fed, it could probably be seen as encroaching on federal power. So simply getting congress to pass a resolution approving it (which in theory would solve the "consent of congress") wouldn't fly like it would with an interstate compact dealing with something more mundane and less political like water rights, or mutual deal on air pollution between several neighboring states.
Disclaimer: IANAL, this is not legal advice etc.