If it was done state-by-state, then I would expect it to be implemented piecemeal, and only where the party in power in that state thought they could get an advantage. To get it across the board like you described, I think it would have to be imposed on the states.
Possibly so, although the Federal government could still persuade the states to do so if they put their mind to it. They got states to raise their drinking age to 21 by holding Federal highway funds over their head. That didn't require amending the Constitution.
Even when the electoral college result and the popular vote match, changing the system would change the dynamics. A candidate would care just as much about a vote from a state that's solidly going for or against them as they would about a vote from a "battleground" state. Every voter would be worth the candidate's effort and attention.
I tend to doubt that. A wealthy donor will always have more clout than a common voter, regardless of which state they come from. Money drives the electoral process more than anything else, and the vast majority of voters are hypnotized by political commercials and pundits in the media telling them how to vote.
Even many in the government and political elite have essentially acknowledged this to be true, as evidenced by the charges relating to "foreign interference" in the last election. Basically, they're saying that people with enough money to buy technology and media have the ability to influence an election. It was no shock to me, but many have reacted as if they've just found out there's no Santa Claus.
Where does "every voter" figure into this, and why would a candidate care any more about the average voter than they currently do?
And a popular vote for president would be in line with the rest of the system:
- Representatives represent a single district. They're elected by a popular vote of that district.
- Senators represent their state. They're elected by a popular vote of that state.
- The President represents the entire country, and so ought to be elected based on the popular vote of the entire country.
The difference here is that the Representatives and Senators are part of the Legislative Branch. The President is part of the Executive Branch. There's no compelling reason that they would have to be "in line" with each other, especially considering that the Judicial Branch is totally unelected.
It's also the same with most of the rest of the Executive Branch - the Cabinet, the Joint Chiefs, FBI Director, etc., who are also unelected.