In almost every county across California, regardless of its political leaning, at least one in ten people has health coverage because of the Affordable Care Act.

And in some counties, almost one-fifth of the population is eligible for insurance under the health law, either through the expansion of Medi-Cal or Covered California, the state-run health insurance marketplace that offers subsidized private coverage.

An examination of data from the state agencies that administer Obamacare in California showed that as of July, over 5 million Californians — about 12.9 percent of the state’s population — had coverage they could lose if the main pillars of the federal law were scrapped. Health care advocates say the high number of Californians with publicly-funded health care shows there are a lot of low-income people in the state.

"They can’t afford to buy their own health coverage or [they’re] not getting it from their employer," said Deborah Kelch, executive director of Insure the Uninsured Project.

About 3.7 million Californians who weren’t eligible before Obamacare now have Medi-Cal. Almost any single adult citizen who earns up to 138 percent of the federal poverty level, or $16,400 in 2016, can get Medi-Cal. Before January 2014, only adults earning up to the federal poverty line were eligible, and single adults without children were excluded altogether.

An additional 1.4 million Californians now have private insurance through Covered California, and nearly 89 percent of them receive federal subsidies to help pay their premiums. As the map below shows, some counties would see big changes under a repeal of the Affordable Care Act — a hallmark campaign promise of President-elect Donald Trump.

Los Angeles County has the highest number of people covered under Obamacare. About 1.5 million residents, 15 percent of the population, have health insurance either through the Medi-Cal expansion or a Covered California plan.

More than 250,000 people in both Riverside and San Bernardino counties could lose coverage in the case of repeal. In Orange and San Diego counties, a total of nearly 778,000 people would be at risk of losing coverage.

In the northern coastal counties of Humboldt and Mendocino, almost one in five people have insurance either through the Medi-Cal expansion or Covered California.

In some counties, fewer than 10 percent of the population signed up for coverage under Obamacare: San Mateo County in the San Francisco Bay Area; Napa County, in one of the state’s best-known wine growing areas; and Placer and Lassen counties in the Sierra Nevada.

Kelch said if coverage is repealed, California policymakers will need to discuss options for replacing it.

People who find themselves uninsured "would fall back to whatever safety net exists in their community," she said, adding that their health care experience could be very different depending on where they live.

This story was produced by Kaiser Health News, an editorially independent program of the Kaiser Family Foundation.