LOS ANGELES (CBS SF/AP) – Enrollment for President Barack Obama’s health care reforms kicks off in October, but many Californians have only a glancing familiarity with details of the plan, which is intended to bring coverage to millions of uninsured Americans, according to a poll released Tuesday.

One in four state voters knows little or nothing about the Affordable Care Act, while another 60 percent say they remain only “somewhat knowledgeable” about it, according to the survey from the Field Poll.

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The findings do not isolate the uninsured or under-insured people who would be pulled under the umbrella of the new coverage. However, the poll broadly suggests that the complex program, which Obama signed into law in March 2010, remains something of a mystery to many voters, even if they support its intent.

“It is so complicated even for the experts to understand,” Field Poll Director Mark DiCamillo said. “When you think you know a little more, it raises more questions.”

In addition, the overhaul is aimed at only a slice of residents in a state of roughly 38 million people, so “the public is not that tuned in,” DiCamillo said.

Those who already have health insurance through their employer will see little if any change.

The state agency guiding Obama’s overhaul, Covered California, faces a daunting task trying to reach millions of people without insurance and sway them to sign up while overcoming geographic, language and cultural barriers.

California could see more than $300 million invested in television and online ads, billboards, door-to-door visits and other sales pitches and promotions to convince uninsured residents to enroll.

The telephone poll of about 1,200 voters, supplemented with interviews with nearly 500 minority voters, was conducted from June 26 to July 21. It has a margin of error of plus or minus 2.6 percentage points.

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It found a majority of Californians continue to support the overhaul, bucking national trends that show most Americans oppose it, although opinions differ sharply across party and geographic lines in the state.

For example, Hispanics who live in Los Angeles and vote Democratic are likely to support the health reforms. White Republicans living in inland counties generally oppose them.

Nearly half of white voters oppose the law, but the state’s large combined population of Hispanics, blacks and Asians who largely support it shaped the overall results: 53 percent of voters support the law in California, either strongly or somewhat.

Seventy-five percent of Republicans oppose it, while 77 percent of Democrats support it.

“We certainly have more Democrats than Republicans, and it’s a very partisan issue,” DiCamillo added.

Under the president’s program, people without access to coverage through their jobs can start shopping for subsidized, private insurance in new state markets called exchanges. The exchanges are supposed to transform the way individuals and small businesses buy private health insurance by increasing transparency and competition, bolstering oversight of insurers and injecting hundreds of billions of dollars in taxpayer subsidies.

The benefits begin Jan. 1. Another major piece is a Medicaid expansion to serve more low-income people.

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