Considering how very large states like CA, with very large conservative populations that often don't matter outside of the 3 major cities in the entire state, and Texas, with very large liberal populations that don't matter, because of the highly populated conservative rural areas, their votes would now be more consequential.
The state effect would be completely eliminated. It's actually exactly what you want. This is for federal office, only, where the popular vote is actually important. Keep local, state politics within state-wide voting.
Politics has become far too national as it is (which is funny, because this is the sort of thing that conservatives claim to hate, but love to support again and again with their posturing and voting habits), so it's really a win-win-win for the various party-based paradigms....assuming people are actually honest about the things they claim.