The California Assembly agreed Thursday to allow the Pechanga Band of Luiseno Indians to expand its casino just south of Temecula, clearing a key hurdle after a year of intense negotiations, lobbying and campaign donations by Pechanga and other gambling tribes.

Revised gambling agreements known as compacts would allow Pechanga and four other tribes to add a total of 22,500 slot machines to the 10,000 now on their reservations. The Pechangas' agreement would allow them to add 5,500 slots to the 2,000 they now operate.

The tribes and Gov. Arnold Schwarzenegger signed the compacts in August, just before the end of last year's legislative session, but the Assembly refused to vote on them on such short notice. The state Senate backed them by a significant majority in mid-April, but the Democratic chairman of an Assembly committee said afterward that the compacts wouldn't allow enough oversight of the casinos' financial reports or sufficient protection for casino employees.

The four Southern California tribes relented on financial oversight and a provision on wage garnishing in a series of new agreements released Wednesday afternoon.

The agreements, which gave little ground to the hotel workers group, sent Democratic Assembly members into a series of closed-door meetings Thursday. The union, UNITE HERE, had sought a provision that would make it easier for workers to unionize. The Californian wasn't able to reach union representatives for comment Thursday.

"They were visibly very upset with the vote that just occurred," said Assembly Republican Kevin Jeffries, whose district includes Pechanga.

Republicans, whose rural and suburban districts include most of the state's Indian casinos, have generally supported efforts to expand them. Democrats, whose urban districts are home to large numbers of union workers, have generally been skeptical, though gaming tribes have appeared eager to change that with a campaign of political donations and intense lobbying since August.

"I was surprised to see as much support from the Democrats as we did, considering all the rhetoric we heard on all the labor issues," Jeffries said. "I think (this week's) agreement has done a little bit to appease the Democrats, to whom unions are important, but not key."

The tribes have repeatedly argued that compacts would put billions of dollars into the state's treasury. Pechanga's compact, for example, calls for a contribution of $42.5 million to the state each year, up from $29 million under the current arrangement. The tribe would be obligated to pay an additional 15 percent of net winnings on the first 3,000 machines it adds and 25 percent of net winnings on the next 2,500 machines. The tribe has said the state could reap as much as $3 billion in additional revenue by 2030, when the compact would expire.

Assembly Democrats and a nonpartisan analyst for the Legislature have called those and other tribes' estimates unrealistic. And Pechanga representatives themselves have said that the tribe does not plan to install all -- or any -- of the 5,500 machines right away.

Still, the tribe is rapidly adding to its complex. It opened a small comedy venue in the casino to augment a larger theater there. Bulldozers are now preparing land on the reservation for a golf course.

"We appreciate the support of the legislative leadership throughout this rigorous ratification process," Pechanga Chairman Marc Macarro said in a statement released early Thursday.

"Today, the Assembly ratified our amended compact which will be a cornerstone for future generations of Pechanga," Macarro added in an e-mailed statement released after the vote.

Republican Assembly members and their aides said they believed Assembly Speaker Fabian Nunez was key in rallying Democratic support for the compacts and the new agreement signed Wednesday.

I. Nelson Rose, a Whittier Law School professor who publishes the newsletter Gambling and the Law, echoed that.

"Politically, this shows how much power the casino tribes have won in California," Rose wrote Thursday. "Unions have always been the backbone of the Democratic party … Yet, the side agreement did not even give lip service to protecting workers' rights to organize as they wished."

The tally on the Pechanga vote was initially listed as 61-8, according to a Jeffries aide. Assembly rules allow members to change their votes as long as the changes don't alter the result.

The bill allowing the Pechanga expansion stipulates that the tribe must negotiate its details with Riverside County and the city of Temecula, which border the tribe's 5,500-acre reservation.

Contact staff writer Chris Bagley at (951) 676-4315, Ext. 2615, or cbagley@californian.com.