California's governor has demonstrated virtue, understood as the good we do when no one is watching. With his state and the nation paying no attention to an anti-constitutional campaign to alter how presidents are chosen, Arnold Schwarzenegger has vetoed a bill that, had it become law, would have imparted dangerous momentum to a recurring simple-mindedness.

The bill would have committed California to cast its electoral votes -- today, 55 -- for whichever candidate receives the most popular votes nationally. The commitment would have been contingent on a compact with other similarly committed states, all having a combined total of at least 270 electoral votes.

Such legislation has been introduced in six states and passed by Colorado's Senate. Advocates offer two rationales:

First, California and other states that are not closely contested battlegrounds are not "relevant." (A state with more than one-fifth the electoral votes needed to win the presidency is "irrelevant"? Please.) What is meant is that uncontested states are "neglected" by presidential campaigns, so direct popular election of presidents -- the point of the multistate compact --would increase voter interest in the many states (by one count, 37, 34 and 37 in the last three elections) that are not considered to be swing states.

But it is disproportionate to traduce, by simplification, sophisticated constitutional arrangements just to make campaigns more stimulating for some states. Furthermore, the electoral vote system is a wholesome political market: It provides steady incentives for parties to change their attributes that make them uncompetitive in many states. How long will the GOP be content not to contest California?

The system aims not just for majority rule, but rule by certain kinds of majorities. It encourages candidates to form coalitions of states with various political interests and cultures. Such coalitions can be assembled only by a politics of accommodation. So the Electoral College system discourages attempts to build narrow ideological or geographical majorities. Today the system is helping the Democratic Party by nudging it to be less of a coastal party -- less reliant on a risky 20-state strategy in presidential elections.

The second argument for the multistate compact is: The possibility of the winner of the popular vote losing the electoral vote contest violates the value that trumps all others -- majoritarianism. Well.

Never mind that in 42 of the 46 elections since 1824 (all but 1824, 1876, 1888, 2000) for which we have popular vote totals, that did not happen. Which suggests that the assault on the electoral vote system is driven by simplistic majoritarianism, which would shatter the two-party system that is conducive to temperate politics.

That electoral vote system (combined with the winner-take-all allocation of votes in all states but Maine and Nebraska) makes it very difficult for third party presidential candidates to be competitive. In 1992, Ross Perot won 18.9 percent of the popular vote but no state and therefore no electoral votes. Direct popular election of presidents would be an incentive for fragmentation of the electorate by the proliferation of factional candidacies.

Imagine 2008 with independent candidacies by, say, Colorado Rep. Tom Tancredo (deport illegal immigrants), Pennsylvania Rep. John Murtha (out of Iraq immediately), New York Mayor Michael Bloomberg (independence from the two parties is a virtue) and Jesse Jackson (he would think of a reason). None could win but cumulatively they could prevent the major-party winner from reaching even 40 percent.

And the multistate compact cannot include a runoff provision. That would require a constitutional amendment; 34 senators can prevent a constitutional amendment from being sent to the states for ratification, and many more than 17 of the smaller states benefit from the additional weight the electoral vote system gives them.

It is perverse that the 2000 election, which culminated with the lawyers' riot in Florida, is cited to undermine an electoral vote system that prevented 2000 from being a calamity. If in presidential elections all popular votes were poured into one national bucket, a close election such as the one in 1960, which was decided by fewer votes (118,574) than there were precincts (166,064), would unleash a coast-to-coast frenzy of litigation -- about ballot design, voting hours, alleged voting-machine malfunctions, etc. The electoral vote system quarantines electoral disputes to a few closely contested states.

Under the multistate compact, Californians, who in 2004 supported John Kerry by a 1.2 million popular vote margin, would have seen their electoral votes swell President Bush's winning margin. In 1960 and 1976, too, California's electoral votes would have gone to candidates rejected by Californians.

They should understand what their governor has demonstrated: Sometimes the loveliest word in America's political lexicon is "veto."