Desperate for English-speaking workers, business leaders in a heavily immigrant California city have launched a $4.5 million campaign to persuade residents to learn the language.

The campaign in Santa Ana, where more than three-quarters of residents are Hispanic and less than 15 percent speak English at home, offers free language classes at a community college and take-home study kits.

"Employers have been coming to us saying: 'Look, we don't have enough people to hire that speak English," said Dale Ward, executive vice president of the Santa Ana Chamber of Commerce.

"Two-thirds of our workforce does not qualify for an entry-level job in growth industries because they do not speak English or do not speak English well enough."

Santa Ana, a working-class city 40 miles south of Los Angeles, has long been a magnet for immigrants from Mexico and Latin America. About 76 percent of residents are Hispanic, 11 percent Asian and about 11 percent white.

Ward said that out of about 350,000 residents of Santa Ana, which is the most densely populated city in California after San Francisco, about 313,000 speak a language other than English at home.

Ads touting the education campaign are plastered on buses, bus shelters, grocery stores and elsewhere. Using eye-catching slogans such as "You Work and Work but You Still Can't Make It," the ads try aim to convince immigrants that they can improve their lives in the United States if they learn English.

Ward said the goal of the campaign was to make some 50,000 Santa Ana residents proficient in English by 2009. The local college offering the free English classes has received 366 phone calls since the ads first aired in February, he said.

Though illegal immigration is one of the most divisive issues in the United States, Ward said the campaign has received a positive response.

"We're not into it for political reasons. We're just trying to build a strong work force," he said.