Article II of the Constitution gives states broad authority to decide how their electoral votes are selected and divided among the candidates. In 48 states, the candidate who gets the most votes wins all of the state's electoral votes.
But the Constitution doesn't require that rule. Maine and Nebraska have implemented district-by-district voting. One electoral vote goes to the winner in each congressional district, and the remaining two electoral votes are awarded to the winner of the statewide popular vote...
But is it a good idea? The Framers meticulously crafted an electoral model that reduced sectionalism and reinforced minority rights. Instead, popular voting would favor regions with high voter density and large states over small. "One man, one vote" may be the rallying cry of a democracy; but that is not our form of governance.
We are a constitutional republic; political outcomes are not always determined by majority rule. ... For example, it takes two-thirds of Congress to override presidential vetoes, approve treaties, impeach a president, or expel a member of Congress.
Yes, there are downsides to district-by-district voting. First, it would increase the number and influence of marginal candidates who have little chance to win statewide majorities. Recall 1992, when Ross Perot captured nearly 19 percent of the national vote, but not a single state. If he had won a significant percentage of electoral votes, the election would have been thrown into the House of Representatives.
Second, winner-take-all eliminates the pernicious effect of gerrymandering from presidential elections. Under a district-based system, gerrymandering would impact presidential outcomes as well as congressional results. Third, less populated and closely divided states might attract candidates if the law provided for winner-take-all, but not if electoral votes were narrowly split.
Finally, a practical problem: district-by-district voting would have to be enacted by state legislatures. Because the dominant party would probably lose electoral votes, repeal of winner-take-all would be an uphill battle. - Robert Levy, Cato Institute