Any state that does that effectively takes itself out of the selection process and gives up its power.
There is no way the left could get an amendment passed, too many states would have to vote against their own interests.
However, there’s always the Supreme Court - they could just “interpret” the EC out of the Constitution.
This will never happen. The states would have to ratify a change to the constitution. The small states will NEVER let this happen. And they shouldnt. If the states are so hot to change, they should simply change the state’s rule on how the votes are assessed.