In this Wednesday, May 30, 2012, photo, Angela Laws poses for a photo in Leesburg, Va. Laws, 58, runs a small business that cleans and maintains commercial buildings and figures that she'll remain uninsured if she can't find an affordable coverage option that fits a monthly budget already crammed with payments of $1,203 for rent $530 toward her car.

By TOM MURPHY

AP Business Writer

One of the biggest misconceptions about President Obamas health care overhaul isnt who the law will cover, but rather who it wont.

If it survives Supreme court scrutiny, the landmark overhaul will expand coverage to about 30 million uninsured people, according to government figures. But an estimated 26 million U.S. residents will remain without coverage a population thats roughly the size of Texas and includes illegal immigrants and those who cant afford to pay out-of-pocket for health insurance.

Many people think that this health care law is going to cover everyone, and its not, says Nicole Lamoureux, executive director of the Alexandria, Va.-based National Association of Free & Charitable Clinics, which represents about 1,200 clinics nationally.

To be sure, its estimated that the Affordable Care Act would greatly increase the number of insured Americans. The law has a provision that requires most Americans to be insured or face a tax penalty. It also calls for an expansion of Medicaid, a government-funded program that covers the health care costs of low-income and disabled Americans. Additionally, starting in 2014, there will be tax credits to help middle-class Americans buy coverage.

The Supreme Court is expected to hand down a decision this month on whether to uphold the law completely or strike down parts or all of it. If it survives, about 93 percent of all non-elderly, legal U.S. residents will be covered by 2016. Thats up from 82 percent this year.

Still, millions of illegal immigrants wont qualify for coverage. This population will account for roughly 26 percent of those who will remain uninsured, according to Urban Institute, a nonpartisan think tank.

And many legal U.S. residents will go without insurance, too. About 36 percent of the population that remains uninsured will qualify for Medicaid but wont sign up for various reasons. Others likely will make too much money to qualify for assistance but be unable to afford coverage.

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