Even with the constitutionality of the Affordable Care Act in doubt, many states are positioning themselves to be ready with at least one provision of the federal law: setting up insurance exchanges.

These exchanges — competitive marketplaces that allow consumers to shop for and purchase health care — are required under the ACA. They are supposed to be operational by January 2013, which means they need to be established well before that.

Many states, however, including Maine, are deferring action until the U.S. Supreme Court issues a final ruling on constitutional challenges to the law. Those states could be holding out to their own detriment.

A March study by the Kaiser Family Foundation showed that only 13 states have set up exchanges and three others had firm plans to establish one. Many more are either studying options or simply waiting, but the study said states that fail to act in 2012 are in danger of falling behind.

“The deadline to demonstrate an operational exchange is fast approaching, and even those states moving more aggressively may find it difficult to put all the pieces into place in time to meet it,” the report concluded.

A recent collaborative known as Enroll UX2014 was launched this week to assist states in establishing their exchanges. The initiative offers a template of sorts that allows states to retain control of their own exchanges without the need to invent the wheel on every detail.

The public/private initiative was organized in early 2011 by the California Health Foundation and is backed financially by a group of nonprofits that support the ACA. States involved in this collaborative run the gamut from reliably Democratic, such as New York and Washington, to traditionally Republican, such as Alabama and Kansas.

Maine is not among the states involved in the collaborative, and it’s not clear whether it will take advantage of the group’s work.

The state is one of many that doesn’t have a health insurance exchange, even in skeletal form.

In one of the more partisan battles of the recent legislative session, State House Republicans deferred setting up an exchange. Instead, they passed a bill that creates a network of licensed “navigators” to help Mainers traverse the tricky insurance world. That bill goes into effect only if the ACA is upheld, however. The Supreme Court is expected to issue a ruling later this month on constitutional challenges to the law made by 26 states, including Maine and most others states that are controlled by Republican governors and legislatures.

Rep. Joyce Fitzpatrick, R-Houlton, a member of the legislature’s Insurance and Financial Services Committee, called the GOP-backed bill a preventative measure.

“It protects us a little bit if the government sets up an exchange, because it allows to use approved navigators,” she said.

Doug Dunbar, a spokesman for the state’s Bureau of Insurance, said the bureau is in the process of implementing that new law, but he didn’t have an update on the status.

Rep. Sharon Treat, of Hallowell, the lead Democrat on the insurance committee, said she has been frustrated with Maine’s failure to implement parts of the ACA. If the law is upheld, she said, Maine would not have enough time to set up such a complicated system.

The Kaiser study agreed.

“States that elect to wait until after June 2012 to begin exchange planning may find there are few legislative options remaining given the short timeline,” the report said.

States that don’t set up exchanges at all will turn over control to the federal government. Treat said that would be bad for Maine.

“Even the (Maine) chamber of commerce has called it a missed opportunity that we didn’t set up an exchange,” she said.

Fitzpatrick isn’t so sure.

“As far as we were concerned, the feds were going to make (states) all play by the same rules, so there wasn’t a big benefit to doing our own thing,” she said.