A new study has found it wouldn't cost much to extend the Affordable Care Act's expanded Medi-Cal coverage to the state's illegal immigrants, but critics are dubious.

The analysis was done as SB 1005, or the Health for All Act, is pending in the state Senate. Sponsored by state Sen. Ricardo Lara, D-Long Beach, the bill would make low-income undocumented immigrants eligible for Medi-Cal and create a California Health Exchange Program for the undocumented that would mirror the Covered California exchange from which they're now excluded.

The UCLA Center for Health Policy Research and the UC Berkeley Labor Center on Wednesday released the policy brief, "A Little Investment Goes a Long Way: Modest Cost to Expand Preventive and Routine Health Services to All Low-Income Californians."

Researchers found the net increase in state spending for expanding Medi-Cal was equal to about 2 percent of current Medi-Cal spending.

Specifically, it would rise somewhere between $353 million and $369 million in 2015, and grow to between $424 million and $436 million in 2019.

That's assuming a hike in enrollment of up to 730,000 people next year, growing to up to 790,000 in five years.

Some proponents of the bill had argued that paying for routine preventive care, thereby reducing expensive trips to the emergency room, would save the state money in the long run.

Although the study's projections found a net increase in cost to the state, the increase was "modest" and well worth the expense, said report co-author Laurel Lucia, a policy analyst at Berkeley.

"For not very much more, we could cover all Californians who need health care," Lucia said, adding that she thought voters would be able to stomach it politically.

California is already in the vanguard on immigrant rights, Lucia said, pointing to the state's decision to begin issuing driver's licenses to those in the country illegally.

Plus, the state and federal government already pay for pregnancy and emergency care for the undocumented, so public funding of health care for those in the country illegally is not unprecedented, Lucia said.

Civil rights activist and United Farmworkers of America co-founder Dolores Huerta applauded the report and said she hopes the Health for All Act becomes law.

"Health care is a right. It's not a privilege," she said.

Republicans in Sacramento are generally opposed to the bill, saying it rewards law breakers and will cost too much at a time when the state can ill afford new spending.

State Sen. Jean Fuller, R-Bakersfield, said the cost and enrollment projections in the report were unrealistic and she looks forward to the Legislative Analyst's Office weighing in.

"You have to remember, not only would we have California's undocumented, but this would probably make us a magnet for the undocumented from other southwestern states and even draw from other countries," Fuller said.

"We're struggling to keep California competitive as it is," she added. "There are so many problems we want to fix for our own living conditions. This is probably not something I would be able to support."