Popular vote of whom? The nation? No, they are electors of a states’ constituency, not the nation at large. That would go beyond faithless to well past feckless. Whole states would be w/o representation if this ever happened.
Well, the national popular vote is what they are trying for, at least those that are wanting to eleminate the electoral college.
Your point of whole states being disenfranchised is well taken and is why I believe that the majority vote of a congressional district should represent that district.
Yes. Several states have voted to give all their electorial votes to the nation's popular vote.