LOS ANGELES — Governor Schwarzenegger of California endorsed Senator McCain in the Republican presidential race today, praising him as an “extraordinary leader” who can reach across the political aisle to get things done.

At a news conference, Mr. Schwarzenegger said Mr. McCain has the national security credentials to do the job, and is a “crusader against wasteful spending.”

Mayor Giuliani also attended the event, one day after he dropped out of the race and threw his support behind his longtime friend.

Mr. McCain is counting on both men — Mr. Schwarzenegger in California and Mr. 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.

Mr. 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.

Mr. 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 American dependence on foreign oil, he added.

Mr. Schwarzenegger’s endorsement of Mr. McCain is yet another setback for the former Massachusetts governor, Mitt Romney, who saw Florida slip from his grasp Tuesday after Mr. McCain rolled up the support of that state’s two top elected Republicans, Governor Crist and Senator Martinez.

Mr. Giuliani’s impact was being felt, as well, when several of his former supporters in New Jersey threw their support to Mr. 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.