US slot manufacturers are purportedly ready to increase their production efforts following the news that California voters have approved a gambling expansion that could add up to 17,000 machines at four of the state's largest Native American Indian casinos.

Up to 10,000 slot machines could be shipped to California over the next 12 months. "This is like adding an entire new state into the mix," said Chuck Brooke, senior vice president of government relations for International Game Technology.

The outcome translates into a 27 percent increase in the California slot machine market.