President Obama's impending executive action on immigration apparently won't bestow health care benefits on millions of undocumented immigrants, according to an individual familiar with the decision.

That means the millions who will be protected from deportation won't be eligible to purchase subsidized coverage from the public health insurance marketplaces established under the Affordable Care Act.

The decision will disappoint advocacy groups, but it doesn't come as a total surprise. The Obama administration passed on a similar opportunity two years ago to extend health-care eligibility to so-called "dreamers," illegal immigrants who entered the United States as children. In September, the Obama administration said it cut off ACA marketplace coverage to about 115,000 immigrants who failed to provide proof of their citizenship or immigration status. And many Hispanics, who have the highest uninsured rates of any group, are hesitant to sign up for Obamacare coverage for fear of an undocumented relative being deported as a result.

Extending government health care to undocumented immigrants has been a lightning rod in the Obamacare debate since it was drafted in Congress. Rep. Joe Wilson's (R-S.C.) infamous "You lie" moment was in direct response to President Obama's assertion that his health-care plan wouldn't insure illegal immigrants.

The truth is that the government already funds some care for undocumented immigrants and has been for years before the ACA. It's through a program that's known as "emergency Medicaid," which pays hospitals to provide emergency and maternity care to immigrants who'd 1) otherwise be Medicaid eligible if they weren't in the country illegally or 2) are legally present in this country but haven't been here for at least five years. As my colleague Sandhya Somashekhar reported last year, the federal government paid out $1.3 billion for this program in 2011, and states paid out hundreds of millions more from their own budgets. That program will grow in the states that have expanded their Medicaid programs under the ACA.

Previous estimates from the Congressional Budget Office found that between 7 million and 8 million undocumented immigrants will remain uninsured under the ACA. They still have limited options for insurance: They can buy coverage through an employer if it's offered, they can purchase directly from an insurer (but not receive federal subsidies), or receive care from Federally Qualified Health Centers. Some states do extend benefits to undocumented immigrants, but they still face greater barriers to care.

However much Obama's executive order may change the lives of these immigrants overnight, their health care will remain the same for most — as if the ACA never happened.