By Cherri Gregg

PHILADELPHIA (CBS) – When the US Supreme Court upheld the Affordable Care Act last June, they created a glitch that could leave poor Americans without coverage, while providing benefits to legal immigrants.

When the framers of Obamacare drafted the law, they assumed that all states would expand Medicaid to include poor citizens not currently covered. After all, the program pumps millions into the states as an incentive. But then the Supreme Court stepped in and put a kink in the system.

“The Supreme Court came along and said, ‘states, you do have the option. You don’t have to expand Medicaid if you don’t want to,’” says Drexel Law professor Robert Field, who has spent months lecturing on the Affordable Care Act.

He says if a state opts out of the Medcaid expansion program, Americans who are too rich to get Medicaid, but too poor to afford subsidies will fall into a donut hole and be left with no coverage. But poor legal immigrants in the country less than 5 years who do not qualify for Medicaid, will still be eligible for federal health insurance subsidies.

So far, 10 states have opted out.  Field says it leaves governors in undecided states in a political quandary.

“A lot of Republican governors have political qualms with going along with it,” he says. “This could push them over the edge and make them say, ‘okay, I’ll go along with it.’”

Field says some governors object to Medicaid expansion for political reasons, others for cost reasons.  Either way, he says it could cause a political firestorm if legal immigrants have access to healthcare that citizens do not.

So far, Delaware has opted in. New Jersey and Pennsylvania are still undecided.