That's the endemic problem of the electoral college; most people, even politicians, don't understand why it is to their benefit, especially if they come from a smaller state.
If this actually goes into effect, there will be only a few states that control presidential in the United States: California, New York, Pennsylvania, Illinois, Ohio, Michigan, Florida, and one or two others. The 11 most populous states control 271 electoral college votes, and six of them are traditional liberal strongholds.
Candidates won't even have to pay lip service of campaigning in states like Indiana, New Hampshire, etc.