Commonwealth found that carriers are responding to the idea and are competing for small business health insurance clients. Seventeen states and the District of Columbia chose to operate their own SHOPS; the feds run them in the other 33. Commonwealth found a perhaps unexpected strength in the system so far.

"In 2014, most state-based SHOP marketplaces will offer small employers a key feature generally not available outside the SHOP: the ability to offer employees a choice of plans from multiple insurers while making predictable contributions toward cov­erage," the report said.

Commonwealth said it was too early to evaluate employer participation in SHOPS because "small employers do not have a deadline by which they need to enroll in coverage, and many may have chosen to renew their existing coverage prior to the availabil­ity of the SHOP, which may also be reducing initial demand for SHOP coverage in some states."

So far, Commonwealth found, no SHOP template has emerged.

"States have varied in their implementation of employee choice and contribution models," the report said. And plan options varied widely as well. "There was wide variation in the total number of plans offered, from 12 in Connecticut to 267 in the District of Columbia, with a broad selection of plans across the bronze, silver, gold, and platinum coverage levels, or metal tiers, out­lined in the Affordable Care Act."

But one early measure of success has been the large insurers' acceptance of SHOP.

"Most states were able to attract at least one of the three largest insur­ers (measured by market share) in the state. Insurers' participation decisions may have varied by the design choices states made and by the existing characteristics of each state's small-group market."

Commonwealth found that most states are developing tools, online and otherwise, to support SHOP adoption, and said such support will be critical to the eventual success or failure of the system. "The degree to which small employers find the SHOP marketplace user-friendly and cost-effective will be critical factors in determining whether they offer coverage through the SHOP, outside the SHOP, or not at all."

Overall, Commonwealth found that the trend was the friend of the creators of the system.

"While not all SHOP marketplaces are yet functioning as intended, their establishment offers an opportunity to identify successful strategies for improving the affordability and accessibility of coverage for small employers," it said.