This time last year, as a rookie candidate, Arnold Schwarzenegger had just stepped onto the campaign trail. He had vague policy views, an arsenal of quips from his action films and a great tan.

No one knew if he was ready for prime-time politics.

Republicans have no doubts now. Party leaders are planning to showcase the California governor in one of the more coveted speaking slots at the Republican National Convention in New York and are stage-managing his schedule with meticulous care.

Nine months into his term as governor of the nation's most populous state, and basking in the kind of political celebrity most politicians can only dream about, Schwarzenegger is emerging as a potentially powerful asset to Bush in the presidential campaign. But his role is still uncertain -- and could prove to be awkward for both men inasmuch as they have different views on abortion, gay rights, gun control, stem cell research and other social issues.

"Arnold could be one of the Republicans' best weapons," said Bill Whalen, a fellow at Stanford University's Hoover Institution who advises GOP campaigns. "He is a vote getter and a crowd pleaser. He's a winning face for the party. And he's one of the only politicians in America who can parachute into any state and cause a stir."

Schwarzenegger's address to GOP delegates and a national television audience Tuesday evening may be his biggest political splash since his resounding victory last October in California's recall election. It also promises to be a rare moment in his new political life in which he strikes a partisan tone.

Since he took office, Schwarzenegger's moderate views and bipartisan habits have at times appeared to charm Democrats in the state legislature more than Republicans. He did not attend the convention the California Republican Party held this month, and he has hardly campaigned for Bush.

Those choices have prompted some political strategists to wonder whether Schwarzenegger and Bush have an uneasy or merely cordial relationship, but aides to the governor scoff at such speculation. They say Schwarzenegger's convention speech, still a closely guarded secret, will demonstrate otherwise.

"His speech will be effusive in support of the president," said Rob Stutzman, Schwarzenegger's chief spokesman.

Republicans are counting on it. Schwarzenegger, they say, could lure more voters to tune into the convention than any other speaker.

"I can't think of anyone else that non-political junkies will go out of their way to watch," said John J. Pitney Jr., a professor of government at Claremont McKenna College in Southern California. "No one is going to say, 'Wow, Senator Zell Miller is speaking? Cool.' Schwarzenegger brings eyeballs."

GOP strategists are also hoping Schwarzenegger will show more interest in campaigning for Bush in California and battleground states, even though he suggested recently that his duties as governor might keep him too busy.

California, with 55 electoral votes, looks like a lost cause for Bush. Polls show Sen. John F. Kerry (Mass.), the Democratic presidential nominee, with a double-digit lead and suggest most voters have made up their minds.

Bush has yet to spend money on television ads in the state, which he lost by more than 1 million votes in 2000, but he is vowing to campaign here. Republican leaders in California say they are holding out hope that Schwarzenegger's uncommon success appealing to Democrats and independent voters will make the race competitive.

His impact is already being felt. GOP candidates have been routed in most statewide elections in California for nearly a decade, but the party is showing new vigor. It has raised about $24 million this year -- twice as much it did during the last presidential election year. It also has registered several hundred thousand new Republican voters since Schwarzenegger's election.

"Having him has been huge," said George "Duf" Sundheim, chairman of the state GOP.

Democrats still hold a decisive voter edge in California -- they constitute about 43 percent of the electorate, compared with 35 percent for Republicans. But Gerald Parsky, the chairman of Bush's California campaign, said he believes Schwarzenegger could almost single-handedly improve the party's prospects in November if he campaigns fervently for Bush.

"We need to attract non-Republicans, and Schwarzenegger has a unique appeal to that group," Parsky said. "He showed that he could attract them last fall, and those voters are still with him."

A poll released this month by the nonpartisan Public Policy Institute of California showed that two-thirds of the state's voters approve of the job Schwarzenegger is doing as governor. Only about 42 percent of California voters, however, say they approve of the job that Bush is doing.

Schwarzenegger is still such a political newcomer that he has yet to move to Sacramento, the state capital. His positions on an array of issues also are not yet clear. But he is constantly casting himself as a nonpartisan reformer.

He has put liberal Democrats in the top ranks of his administration and is showing willingness to compromise with Democratic leaders over almost any issue but taxes -- which he has refused to raise. That style is frustrating some Republican lawmakers. Only a few GOP state senators voted last month to support his first budget. Some said it reflected the same spending habits of the governor he deposed last year, Democrat Gray Davis.

"Arnold's really dancing around most partisan issues," Whalen said.

But at a Republican fundraiser in Santa Monica earlier this month, Schwarzenegger made a rare appearance at Bush's side.

"It's fantastic to be with all of you here tonight to salute our great president," the governor told a crowd of about 500 GOP donors. He added that he has been working hard on Bush's reelection.

"I've been organizing Austrian former bodybuilders for Bush-Cheney. I've been organizing girlie men for Bush-Cheney," he said, invoking a term he used this summer to deride Democratic legislators.

Some political analysts say Schwarzenegger could be more valuable to Bush's campaign outside of California -- particularly in swing states such as Ohio. For the past 15 years there, he has presided over a fitness expo and bodybuilding contest that now draws about 70,000 visitors.

Rep. David Dreier (R-Calif.), who is close to Schwarzenegger, said that if the governor campaigns for Bush in battleground states, he has the potential to sway a few thousand votes -- which may be enough to affect the outcome of the election in those places. "I think he could have a tremendous impact," Dreier said. "If he's needed, he's going to be there."

But Schwarzenegger's presence also could bring risks to Bush, some political analysts say. "If they make joint appearances, they are always going to be asked about their differences on subjects like abortion and gay rights," Pitney said.

Aides to Schwarzenegger say his convention speech will not focus on controversial policies. Instead, he intends to promote his biography as a symbol of the American dream and to make a case for reelecting Bush.

Otherwise, Schwarzenegger plans to keep a relatively low profile during the convention. He is planning to visit an after-school program in Harlem and to attend a tribute that entertainment industry leaders are giving him. He is not scheduled to meet Bush and may leave the convention early and watch the president's speech from California.

To keep the spotlight on Bush, Schwarzenegger also is making what for him may be the ultimate sacrifice: He is vowing to turn down interview requests from national media in New York and to avoid cameras.

Arnold Schwarzenegger has been known for reaching out to Democrats, appointing several to top posts in his administration.President Bush and Schwarzenegger made a rare joint appearance at a recent fundraiser.