Relatively few states have made progress in establishing the health insurance exchanges that represent a central piece of the federal health care reform bill, raising fresh doubts about the future of President Barack Obama's signature domestic achievement.

The health care overhaul envisioned a comprehensive network of 50 state-run insurance exchanges that would allow customers to compare prices and, in theory, keep insurers honest by providing a healthy dose of competition. But only about a third of states are on track to have the exchanges operational by the 2014 deadline, raising the possibility that the federal government will need to intervene.

When this law was passed in the spring of 2010, people really believed the states would get on board and we would see almost all exchanges being state-run, Timothy Jost, an expert on health policy at Washington and Lee University, told The Washington Post. But there is a growing concern that quite a number of states will not be ready.

In many cases, Republican governors or state legislatures have openly defied the insurance exchange mandate. Gov. Rick Scott of Florida, a Republican, has rejected any federal money allocated by the Affordable Care Act, while the Republican governors of Oklahoma and Kansas have returned millions of dollars intended to facilitate the exchanges. Even New York, a reliably left-leaning state with a popular Democratic governor, has seen its Republican controlled state Senate refuse to act.

I would fight very vociferously to make sure that we're not seen as implementing and expediting Obamacare, Republican State Senator Gregory R. Ball told The New York Times.

Ball said that the stalling tactic accounted for the possibility of Obama losing the 2012 election to a Republican candidate who would then roll back the health care law. Other state lawmakers are awaiting the outcome of pending legal challenges to the law, of which one is widely expected to reach the U.S. Supreme Court. Even some Democratic state lawmakers have avoided enacting the exchanges, fearing an election day reprisal from constituents.

Somehow, along the way, this got tagged as supporting 'Obama care,' Arkansas state Rep. Fred Allen (D), whose exchange bill died in Arkansas' Democrat-controlled assembly, told The Post. And I think that made a lot of Democrats afraid to sign on with it.

If states have not made sufficient progress in launching their own insurance exchanges by 2013, the federal government would have to step in. That could limit respective states' ability to make decisions about pricing and coverage.