With National Popular Vote, big cities would not get all of candidates’ attention, much less control the outcome.
The population of the top five cities (New York, Los Angeles, Chicago, Houston and Philadelphia) is only 6% of the population of the United States and the population of the top 50 cities (going as far down as Arlington, TX) is only 19% of the population of the United States. Suburbs and exurbs often vote Republican.
If big cities controlled the outcome of elections, the governors and U.S. Senators would be Democratic in virtually every state with a significant city.
A nationwide presidential campaign, with every vote equal, would be run the way presidential candidates campaign to win the electoral votes of closely divided battleground states, such as Ohio and Florida, under the state-by-state winner-take-all methods. The big cities in those battleground states do not receive all the attention, much less control the outcome. Cleveland and Miami do not receive all the attention or control the outcome in Ohio and Florida.
The itineraries of presidential candidates in battleground states (and their allocation of other campaign resources in battleground states) reflect the political reality that every gubernatorial or senatorial candidate knows. When and where every vote is equal, a campaign must be run everywhere.
Even in California state-wide elections, candidates for governor or U.S. Senate don’t campaign just in Los Angeles and San Francisco, and those places don’t control the outcome (otherwise California wouldn’t have recently had Republican governors Reagan, Dukemejian, Wilson, and Schwarzenegger). A vote in rural Alpine county is just an important as a vote in Los Angeles. If Los Angeles cannot control statewide elections in California, it can hardly control a nationwide election.
In fact, Los Angeles, San Francisco, San Jose, and Oakland together cannot control a statewide election in California.
Similarly, Republicans dominate Texas politics without carrying big cities such as Dallas and Houston.
There are numerous other examples of Republicans who won races for governor and U.S. Senator in other states that have big cities (e.g., New York, Illinois, Michigan, Pennsylvania, and Massachusetts) without ever carrying the big cities of their respective states.
The National Popular Vote bill would not change the need for candidates to build a winning coalition across demographics. Candidates would have to appeal to a broad range of demographics, and perhaps even more so, because the election wouldn’t be capable of coming down to just one demographic, such as voters in Florida.
Nope. Campaigns are affected by population density: the more people per square shouting distance, the more voters can be persuaded per shout. Given limited resources, it's far more efficient to campaign in Miami FL than Jackson WY. ...unless the WY votes have more weight than in a popular vote, then it becomes worth a candidate's while to at least show up once.
Run the numbers, and you'll see that NPV will render most states - ones that tend to vote Right - impotent in elections.
Your theory works where resources can be distributed efficiently throughout the region, and where population gradients are workable. More important, it presumes a continuous jurisdiction; we are the United States, and a national popular vote proceeds to erase those precious boundaries. (Trust me: NY would outvote GA every time, and having lived in both I sure don't want NY sensibilities imposed on GA.)