It needs a constiitutional ammendment.
Those are very hard to get and this would be even more so. All the states with low populations would say "NO!"
But you're right what we have now is not fair in a presidential election.
"There is a cult of ignorance in the United States, and there has always been. The strain of anti-intellectualism has been a constant thread winding its way through our political and cultural life, nurtured by the false notion that democracy means that "my ignorance is just as good as your knowledge."
-- Isaac Asimov