ObamaCare's supporters say there's no evidence "navigators" will be a source of fraud and argue that GOP's rules ultimately seek to hamper outreach under the law.
"This is what we call navigator suppression," HCAN Executive Director Ethan Rome said on a call with reporters.
"The Republicans argue these laws are about protecting consumers … But really they're hurting real people with real healthcare needs."
The Obama administration is hoping to sign up several million people over the next six months for the new insurance marketplaces.
"Navigators" affiliated with churches, community groups and hospitals are expected to play a large role in helping consumers understand their options on the exchanges.
At least 18 states have taken steps to restrict the counselors' activities or impose additional training.
In Missouri, for example, one statute prohibits "navigators" from carrying out their express role of giving "advice concerning the benefits, terms and features of a particular health plan."
The Florida Department of Health recently prohibited "navigators" from conducting outreach activities at county health departments.
And several red states have imposed criminal background checks and examination requirements above what's mandated by federal law.
The rules have many defenders, including insurance agents who feel the "navigator" program must be highly regulated in order to protect consumers. Republicans in Congress have charged that the program could admit felons as counselors without additional scrutiny.
But critics say the requirements are causing "navigator" grantees to drop out because of excessive red tape.
At least one organization also returned its funding after receiving an expansive preliminary inquiry from Republicans on the House Oversight Committee.
Sabrina Corlette, a health policy expert at Georgetown University, called the state laws "unprecedented" and unnecessary given Medicare's positive history with counselors similar to "navigators."
"It's not to say there aren't legitimate concerns about fraud, or con artists taking advantage of ObamaCare," Corlette said.
"It's just that these state laws are really barking up the wrong tree … There is no credible evidence whatsoever that 'navigators' will be a source of fraud."