Slightly more than 8,000 individuals had signed up for insurance through President Obama's health care law in Massachusetts by the end of January, representing only 5 percent of the original target of 155,000.

On the flip side, according to a new report by the Department of Health and Human Services, Connecticut signed up nearly 50,000 individuals for coverage, which is more than double the original target of about 20,000.

The stories of Massachusetts and Connecticut are part of a larger trend in which there is a wide disparity among the states when it comes to how enrollment is progressing. State-by-state performance data is crucial to assessing the success or failure of the health care law.

To have a chance at success, Obamacare's insurance exchanges need to enroll enough individuals to make them viable, and a critical mass of enrollees must come from a young and healthy demographic. But the insurance risk pool isn't a national one. That means that to fully succeed, the health care law needs to attract a sufficient number of enrollees in all 50 states, plus the District of Columbia.

Looking at the attached table, which includes a state-by-state breakdown of HHS's original enrollment targets and compares them to sign up numbers the agency released on Wednesday, what becomes clear is that some states are meeting or even exceeding their enrollment targets. But others are well below their targets.

In 11 states including Connecticut, Rhode Island, New York, Maine and New Hampshire, signups are more than 100 percent of projected enrollments. On the other hand, in 13 states signups are tracking at less than 50 percent of original targets.

Though supporters of the health care law have tried to point fingers at Republican states for trying to sabotage enrollment efforts, the worst-performing states were among those that were most gung-ho about implementing the law, including Massachusetts, Oregon, Maryland and the District of Columbia.

If these numbers hold up, the could lead to some interesting decisions for insurers, who may try to back away from exchanges in states that haven't proved viable, while increasing the number of carriers offered in other states.