While there, Tavenner apologized.
"To the millions of Americans who've attempted to use Healthcare.gov to shop and enroll in healthcare coverage, I want to apologize to you that the website has not worked as well as it should," she said. "We know how desperately you need affordable coverage."
While remaining hard to pin down, insisting repeatedly the committee would receive specific statistics on enrollment no sooner than mid-November, Tavenner both tempered expectations and cautiously lauded improvements to the online exchanges.
"We expect the initial number [of enrollees] to be small," she said. Still, the site "can and will be fixed," she said, adding that "we are seeing improvement each week."
Tavenner, who runs the Centers for Medicare and Medicaid Services, pinned much of the blame on contractors who worked on building Healthcare.gov, not mismanagement from her office.
“CMS has a track record of successfully overseeing the many contractors our programs depend on to function,” she said in her prepared statements. “Unfortunately, a subset of those contracts for HealthCare.gov have not met expectations.”
Tavenner was installed as chief of the CMS in May by a 91 to 7 vote in the Senate. Many believed her appearance before a House committee, led by Republicans who have voted more than 40 times to repeal or delay the Affordable Care Act, would be much easier than the hostile one expected Tuesday for her boss, Secretary Sebelius.
She has said she has no plans to leave.
Notable deaths of 2014 [PHOTOS]