When you talk to politicians about the national popular vote very quickly almost everyone will say, why would a state give up the influence on the outcome of the presidential election that comes from the winner-take-all system? Why would politicians in that state pledge its electors to the winner of the national popular vote?

The question is based on a false premise that is hardly ever discussed. The winner-take-all system gives no weight to any votes in a state beyond the single one that provides the plurality. If 62% of the people in California vote for the democratic presidential candidate, then 11.9% or in other words more than one out of every five of those voters have no impact on the outcome of the presidential election. They are surplus. For that reason the Democratic presidential candidate does not try to maximize turn out in California. The Democratic campaign ignores the state. Instead of maximizing the influence of the state’s voters, this system of not counting votes in a grand national winner-always-wins way actually minimizes them. 

In addition, the winner-take-all system hurts the party that has the most support in a state because it disincentivizes that party’s efforts to persuade non-voters to support the party. Worse than that, the non-voters increasingly feel the winning party doesn’t care about them. They become like a free radical, susceptible to attachments of dangerously unpredictable chemistry. They threaten the ruling party’s future. 

Some may remember that California used to be a Republican stronghold. But the Republican Party in California did not maximize its own turn out, minimized its appeal to different factions, and then in the early 1990s chose not to pay attention to non-voting citizens who were born in other countries. The result was that an opportunity was created that the Democrats took.  They repositioned their party to capture the nonvoters and the ignored factions. They became the ruling party in California for the last quarter century. 

But because so many millions of Democratic voters in California are ignored by the presidential selection system, California Democrats now cannot deliver to their supporters the kind of impact in Washington that the voters demand. And they cannot make the case for maximizing turn out.

This is the reason California Democrats supported the National Popular Vote Interstate Compact. For the same reason every ruling party in every state should want the presidential candidate of their party to compete for votes in their state. The winner take all system discourages exactly that. 

In short, a party in power in a state is well advised to maximize participation in voting. And the best way to do that by far is to support the national popular vote. Other measures are useful, like easier registration or enfranchising the disenfranchised. But assuring that both campaigns strive to win the national popular vote will increase turnout by an extra order of magnitude relative to all other voting reforms.