(CBS/AP) -- California Gov. Arnold Schwarzenegger endorsed Sen. John McCain in the Republican presidential race on Thursday, praising him as an "extraordinary leader" who can reach across the political aisle to get things done.
At a news conference, Schwarzenegger said McCain has the national security credentials to do the job, and is a "crusader against wasteful spending."
Former New York Mayor Rudy Giuliani also attended the event, one day after he dropped out of the race and threw his support behind his longtime friend.
McCain is counting on both men - Schwarzenegger in California and Giuliani in New York - to help propel him to victory in the two biggest states holding primaries next week. Combined, they offer 271 delegates, more than a quarter of the 1,023 at stake in a Super Tuesday slew of primaries and caucuses.
"This isn't an endorsement that's going to help McCain smooth concerns that conservatives have about his candidacy," said CBSNews.com senior political editor Vaughn Ververs. "But it's further evidence of a coming together among establishment figures behind his campaign, and in the Republican Party, that's worth plenty, especially in large Super Tuesday states like California and New York."
Schwarzenegger delivered his endorsement after a tour of a solar-energy company. he said it's the kind of factory that helps protect the environment while helping the economy. "That's music to my ears," he said.
McCain pledged he would work to leave the planet in better shape than it currently is. He has been a supporter of efforts to deal with global warming.
"Green technologies is one of the key ways" to reduce U.S. dependence on foreign oil, he added.
Schwarzenegger's endorsement of McCain is yet another setback for Mitt Romney, the former Massachusetts governor who saw Florida slip from his grasp Tuesday after McCain rolled up the support of that state's two top elected Republicans, Gov. Charlie Crist and Sen. Mel Martinez.
Giuliani's impact was being felt, as well, when several of his former supporters in New Jersey threw their support to McCain earlier in the day.
New Jersey has 52 delegates at stake in next week's primary, and like New York, gives them all to the winner of the popular vote.
His strategy uncertain, Romney plans to offer himself as the conservative alternative to McCain as he pushes ahead in hopes of winning enough delegates to topple the Arizona senator when 21 states vote in the Republican contest on Tuesday.
Both McCain and Romney have signaled they intend to air television ads in at least some of the states on the ballot.
Former Arkansas Gov. Mike Huckabee and Texas Rep. Ron Paul are also on the ballot.
Schwarzenegger's move comes as McCain plows toward the nomination, the only Republican candidate to have won three hotly contested primaries - New Hampshire, South Carolina and Florida - since voting began earlier this month.
"Governor Schwarzenegger is an exceptional governor and we are honored that he has decided to endorse Senator McCain, and look forward to the event tomorrow," said Steve Schmidt, a senior McCain adviser who managed Schwarzenegger's 2006 campaign.
Schwarzenegger sat in the audience Wednesday as McCain and Romney shared a debate stage with Huckabee and Paul at the Ronald Reagan Presidential Library.
McCain, the four-term senator, is running strongly ahead of all three in California. Candidates secure three delegates for each of the state's 53 congressional districts they win in the primary, in which only Republicans can vote.
The ultimate effect of Schwarzenegger's endorsement is unclear. The celebrity governor and former actor is universally known in the state, and his political network certainly will be helpful to McCain, who has virtually no organized effort in California after his candidacy nearly collapsed last summer. The actor-turned-governor also is a prolific fundraiser.
But Schwarzenegger has a strained relationship with some conservatives in his own party and McCain, himself, is fighting to convince GOP rank-and-file that he's committed to conservative values. Schwarzenegger's nod could exacerbate concerns about McCain among the party establishment.
Schwarzenegger also is taking heat from state Republicans who argue he's been too willing to bend to the wishes of the Democratic-controlled Legislature. At the same time, California faces a $14.5 billion budget deficit over the next year-and-half, and the governor has rankled the state's powerful education lobby with his proposal to cut spending by 10 percent from state agencies to deal with the financial crisis.
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