Really, electors should vote based on popular vote? As if a Republican Party elector would just give the presidency to Clinton. Also, popular vote is a much more flawed system because it promotes urban centrism. Philippines uses popular vote so therefore, Manila became the centre of stage in politics because it has the highest population in the Philippines. The rural areas are ignored. If America uses popular vote, the rural voters will be ignored much like in the Philippines. The interests of the politicians will revolve around the cities.

 Therefore, electors should vote based on their states' interests, not popular vote.