It's important to understand that the alternative to the electoral college is not just "popular vote", but a vote of the representatives of CONGRESS. Those were the alternatives that were being considered by the Founding Fathers. Remember, there is no other election we have that is truly national; EVERY other election is handled on the state or local level, and that is a specific throwback to the sanctity of states rights. In this age of instant communication, and flash travel, we have minimized in recent times the power of states and the obligation of STATES to implement the will of the people, not the Federal government. But in that light, we have to equally protect the rights of the STATES almost as much (but not as much) as the rights of the people. So what happens is, as states grow smaller, they have disproportionally greater power, but at the other end, where presumably the rights of the people are more represented, that doesn't grant those states proportionally more power.
By skewing the power disproportionately to the smaller states, it not only empowers them, but creates incentive for candidates to concentrate on those localities in our nation that are NOT the populist centers. If it was truly proportional, then even though the smaller states would have SOME power, they would not have enough to overcome the mass of populist areas, and the fear is, even though they would have a vote, per se, they wouldn't necessarily have a VOICE, or have the attention of the candidates. Again, not the PEOPLE of that state, but the state itself. By that I mean the policies, geography, industry, and programs of that state. It is also a safeguard against rapid relocation (migration) to/from the cities.