In a year when Republican presidential candidates have aggressively courted the GOP right, Gov. Arnold Schwarzenegger warned Friday that the party faces a perilous future if it continues to surrender the political center.

"Our party has lost the middle and we will not regain true political power in California until we get it back," the celebrity governor told hundreds of Republicans at a state party convention.

"The California Republican Party should be a right-of-center party that occupies the broad middle of California. That is a lush, green, abandoned political space," the governor said. "It can be ours."

The state party's percentage of voter registration has been shrinking, and to reverse it the party must tackle issues with broad public appeal, like climate change and building highways, railroads and tunnels, he said. In an apparent reference to abortion and other social issues that often divide the party, he said members must be accepting of those with other views while not abandoning "who we are."

The actor-governor compared the fall-off in registration to a movie dud. "We are dying at the box office," he said.

The party wins elections and grows by "including, not excluding," the governor said. He recalled Ronald Reagan carried 49 of 50 states in 1984 because he "reached out and captured the political center."

"Defeat does not have to be our future," Schwarzenegger said.

He said he wanted the party to be welcoming to independents — the fastest growing voter group in California. He also said the party should open up its February presidential primary to independent voters — an issue that could come up during the convention.

In a year when many polls show Democrats holding an advantage heading into 2008, it was clear the governor intended his message to have national relevance.

The actor-governor describes himself as a "post-partisan" who wants to bridge the political divide that often leaves the state capital of Sacramento gridlocked.

He recently proposed distilling the state GOP platform — the party's statement of core values — into as little as a single page focusing on lowering taxes, limiting the size of government and building a strong national defense. That proposal, in a letter to party members, made no mention of abortion, gay marriage or other social issues.

The governor received standing ovations before and after the speech. But reaction was divided.

He "wasn't stressing issues that unite us, he was stressing issues that divide us," said Mike Spence of the conservative California Republican Assembly.

Schwarzenegger was followed by Texas Gov. Rick Perry, who delivered a speech strikingly different in tone. He lambasted liberals and Democrats, and stressed his opposition to abortion and same-sex marriage. Texas is "the most pro-life, pro-family state in the nation," he said.