The last day of arguments before the U.S. Supreme Court concerning the constitutionality of the Affordable Care Act focused on Medicaid — the federal-state program that provides healthcare for the poor.

The argument centered on whether the proposed Medicaid expansion, which requires expanded access to Medicaid in exchange for federal funding, is constitutional.

The 26 states opposing the law say they can’t afford to expand their Medicaid rolls so they’ll have to pull out of the program and lose the federal money that helps them run it. Under the healthcare reform law, Medicaid would cover an additional 16 million people, those with incomes up to 133 percent of the federal poverty level.

The Obama administration says the federal government will be picking up most of the tab for the Medicaid expansion. But the states say they’re worried that the federal government won’t follow through on that promise.

But the consequences of a court decision to strike down the law could have far-reaching consequences, consequences for another popular federal program: unemployment benefits. It could also mean changes to the Civil Rights Act and the Clean Air Act, if the decision were written broadly enough.

Megan Hughes, a reporter for Bloomberg News who has been covering the trial, said Justice Sonia Sotemayor brought up this very issue in oral arguments Wednesday, saying she was concerned this sort of ruling would tie the hands of the federal government in a whole host of areas.

"The bigger the problem, the less your powers are, because one of (states' Attorney Paul) Clement's big arguments was the size of this. The fact that it's $3.3 trillion over 10 years, that there should be limits to Congress's power," Hughes said. "Sotemayor said that's going to handicap the federal government from dealing with some of the biggest problems the nation faces."

Hughes said while Tuesday's argument was viewed as a toss-up, Wednesday's was viewed as almost a slam-dunk for the federal government.

"It's an uphill battle for the states. None of the lower court decisions have been in the states' favor," she said.

As precedent, many proponents cite the federal law that required states raise their drinking age to 21 in order to continue receiving all of the federal highway funds.

"There would be so many examples, if the court decided to strike this down, they would have to write it in such a narrow way because it could so easily brush up against so many other federal-state partnerships that already exist," Hughes said.