WASHINGTON: The Centers for Medicare and Medicaid Services is preparing to step in for states that are too far behind to establish the healthcare exchanges mandated by the Affordable Care Act.

The exchanges are marketplaces where consumers buy insurance and insurers sell plans. The Affordable Care Act mandates that states create exchanges by January 1, 2013, so individuals and small employers can purchase coverage from them by the start of the following year.  

If states do not meet that deadline, ...