An Oregon congressman and other legislators on Thursday called for a federal probe of Oregon's deeply troubled Obamacare health insurance exchange, which has been unable to enroll anyone online despite receiving $305 million in federal grants.
"The catastrophic breakdown of Cover Oregon is unacceptable and taxpayers deserve accountability," U.S. Rep Greg Walden, R-Ore., and other leaders of the House Energy and Commerce Committee wrote in a letter to the General Accountability Office, naming Oregon's health exchange.
The request for the GAO probe—which Walden's spokesman said is "likely" given that GAO staff worked with the congressmen on the wording of the letter—is believed to be the first time legislators have asked for a federal investigation of an Obamacare exchange run by an individual state, the spokesman said.
The letter noted that HealthCare.gov, the federally run Obamacare exchange that sells health plans in 36 states, and other exchanges run by individual states such as Oregon, "have encountered numerous problems."
(Watch: Walden's press conference requesting a probe)
"Although the rollout of the Patient Protection and Affordable Care Act has been problematic nationwide, no state has had more complications than Oregon," Walden and the other congressmen wrote. "The state of Oregon's exchange website, Cover Oregon, has been such a technological failure that the site has been unable to enroll anyone months after the start of the open enrollment period."
(Read more: Obamacare changes a negative for insurers: Moody's )
More than four months after its scheduled launch, Cover Oregon's website is not functioning.
The letter's other signatories were House Energy and Commerce Committee Chairman Fred Upton, R-Mich., Health Subcommittee Chairman Joe Pitts, R-Pa., and Oversight and Investigations Subcommittee Chairman Tim Murphy, R-Pa.
"We are aware of this, and have no further comment," Cover Oregon spokeswoman Ariane Holm said in an email response to CNBC when asked for comment.
(Read more: Doctors fear 'crushing' costs from code switch )
Walden's spokesman, Andrew Malcolm, told CNBC, "We do know that the GAO is interested," and that that interest goes beyond just the many problems with Oregon's exchange. A number of other states, including Maryland, Minnesota and Hawaii, have experienced severe problems with their health exchanges since the launch of Obamacare enrollment on Oct. 1.
Malcolm said Cover Oregon has spent at least $160 million to date on the website, which was supposed to be enrolling people in Obamacare insurance plans sold by insurance companies at competitive prices.
The federal government has issued a total of $305 million in grants to Oregon to perform feasibility studies as well as to build, test and operate the exchange. An unknown fraction of those grants have been spent.
"This is an embarrassment for the state to have a website like this that doesn't function," Walden told The Bulletin, a newspaper in Oregon. "It's extraordinary mismanagement."
Cover Oregon's chief executive, Rocky King, resigned for medical reasons in January amid ongoing criticism of the website.
(Read more: Obamacare enrollment rises as more youths join)
Despite the website's troubles, Cover Oregon has managed to enroll nearly 34,000 people in private Obamacare insurance plans through paper applications.
That tally is effectively dead center in the enrollment tallies of all 50 states and the District of Columbia. It also is in the middle of the tallies of the 15 Obamacare exchanges that are being run by individual states and D.C.
—By CNBC's Dan Mangan. Follow him on Twitter @_DanMangan