Ever since the U.S. Supreme Court ruled last summer that expanding Medicaid to more low-income people was optional for the states, the focus has turned to what Republican governors and GOP-controlled legislatures would do.

Would they forego tens of millions of dollars in federal aid that would extend health insurance to many more people and, proponents argue, would provide a major boost to state economies? Or would these governors, many of whom vowed not to expand, stand their ground and insist the federal government will not be able to afford the expansion?

As of May 1, 16 states plus the District of Columbia have approved the expansion or are headed in that direction, 27 have rejected it or about to and seven states could still go either way.

Some Republican governors, including Arizona’s Jan Brewer and Florida’s Rick Scott, have broken ranks, which in some cases has pitted them against GOP majorities in their legislatures. The other major development has been the proposal by Arkansas Democratic Gov. Mike Beebe, who received tentative permission from the Obama Administration to use federal Medicaid dollars to buy health insurance on the private market. And Republican legislators in some states, such as Texas and Louisiana, are interested in exploring similar plans, even as their GOP governors remain fiercely opposed.

With uncertainty about those plans and legislative battles still unfolding in a number of states, it’s not yet known how many states will expand their Medicaid programs come Jan. 1, when the Affordable Care Act is set to take effect. Below is an up-to-date look at where each state and the District of Columbia stand at the moment.

Stay tuned. Much can happen before January.