Last weekend, gubernatorial candidate and California State Treasurer Phil Angelides offered a rabid attack on Gov. Arnold Schwarzenegger before the state Democratic convention. It won him an unexpected two-thirds of the votes from the party’s elites, and thus the endorsement.

Though it is still anyone’s bet whether Angelides or his opponent, State Controller Steve Westly, will receive the party’s nomination in June, California Democrats face a big risk: politicking themselves into irrelevance.

For all of their Left Coast reputation, Californians are largely moderates. They support same-sex rights — but not gay marriage. They support access to abortion — but allow for certain restrictions. And they want social services without the taxes needed to pay for them.

The danger for both Angelides and Westly is that, in courting the party’s fist-shaking liberals, they make themselves unelectable in the November general election against Schwarzenegger. The reason is changing state demographics: Since 2002, the Democratic Party in California has lost one-tenth of its members. In the same period, the number of registered voters who don’t identify with either party now represents nearly 20 percent of the electorate. The winner in November will need to win over this temperate bunch; breathing fire will likely turn it off.

It’s a lesson Schwarzenegger learned last November, when his special election ballot measures alienated much of the electorate. Since then, he appears to have learned from his mistakes, and Democrats would be wise to follow suit. Veering to the hard left will simply ensure that the eventual Democratic nominee gets terminated come November.