2012 Decoded

One aspect of the Supreme Court's decision largely upholding President Obama's health care reform law seems likely to heighten the political argument over the plan in the states.

While upholding the individual mandate at the law's core, the five-member majority led by Chief Justice John Roberts struck down one aspect of the law's expansion of Medicaid, the joint federal-state program providing health insurance for the poor. In so doing the Court virtually guaranteed sharper debate in the states, especially Republican-leaning red states, over whether to join the program the law establishes to expand Medicaid eligibility and coverage.

Those decisions will carry substantial stakes. Many of the conservative states most likely to opt out of the Medicaid expansion are also among the states with the largest number of uninsured. National Journal has calculated that the 26 states that joined the lawsuit against the Medicaid expansion contain 27.6 million uninsured, a 55 percent majority of all the uninsured in America, according to Census Bureau figures. That includes Texas at 6.1 million uninsured, Florida at 3.9 million, and Georgia at 1.9 million.

The health care law required states to expand eligibility for Medicaid to all residents earning below 133 percent of the poverty line. That expansion was expected to provide coverage to about 17 million of the uninsured, roughly half of the total coverage expansion projected under the law. (The mandate on individuals to buy insurance, with substantial subsidies from the government and the establishment of exchanges where they can shop for competing coverage plans, is expected to provide the other half.)