Updated

Health and Human Services Secretary Kathleen Sebelius on Wednesday deflected charges that the administration misled the American people about being able to keep their health plans under ObamaCare -- claiming that despite thousands of cancellation notices, the White House is keeping its promise.

Sebelius testified at a House hearing that originally was called to address the glitch-ridden ObamaCare website. Sebelius personally apologized for those failures and told lawmakers: "Hold me accountable for the debacle. I'm responsible."

Sebelius took the blame for giving the impression that the website was ready for launch before Oct. 1. "I told the president we were ready to go. Clearly, I was wrong," she said.

But Republicans also used the opportunity to press Sebelius on President Obama's repeated claims that people who like their current health plans can keep them under the new law. Thousands of cancellation notices going out to consumers have sharply challenged that claim.

"The news seems to get worse by the day," Rep. Fred Upton, R-Mich., chairman of the House Energy and Commerce Committee, said at the start of the hearing before his committee. From the outset, Upton grilled Sebelius on those notices, asking why a change was made allowing certain insurance policies to be ruled ineligible under ObamaCare.

More On This...

    Sebelius, however, claimed: "There was no change."

    Sebelius laid out a highly nuanced position.

    The secretary denied that Obama had broken his promise and claimed that for the most part, people who had coverage as of March 2010 can keep their current plans -- provided their insurance companies haven't changed them significantly. That wrinkle, however, was rarely explained by Obama before now.

    Though Sebelius and other officials argue that those receiving cancellation notices will be offered better-quality plans, Republicans say it still flies in the face of what the president said over the past several years.

    "Some people like to drive a Ford, not a Ferrari," Rep. Marsha Blackburn, R-Tenn., said. "You're taking away their choice."

    Blackburn asked Sebelius point-blank: "Is [Obama] keeping his promise?"

    "Yes, he is," Sebelius answered.

    Sebelius' appearance is her first before Congress since the troubled launch of the exchange websites on Oct. 1.

    At the start of the hearing, she apologized for the problems with the site.

    "Access to HealthCare.gov has been a miserably frustrating experience for way too many Americans," Sebelius said, vowing to fix the problems.

    To the American people, she said, "You deserve better. I apologize. I'm accountable to you for fixing these problems."

    Sebelius admitted that the testing done before the Oct. 1 launch was "clearly not" enough. "We did not adequately do end-to-end testing," she said.

    Clearing up one mystery, Sebelius said Marilyn Tavenner, head of the Centers for Medicare & Medicaid Services, was the one who made a controversial decision to not allow consumers to browse for policies before logging in. Some have blamed this decision for the system overload earlier this month.

    In written testimony released ahead of Wednesday's hearing, Sebelius vowed to improve the website and said the consumer experience to date is "not acceptable." But she defended the law itself and said extensive work and testing is being done.

    Sebelius was also facing mounting pressure from high-ranking Republicans to resign. Sen. Lamar Alexander, R-Tenn., top Republican on the Senate health panel, was the latest to join the call.

    "Mr. President, at some point there has to be accountability. Expecting this secretary to be able to fix what she hasn't been able to fix during the last three-and-a-half years is unrealistic," he said on the Senate floor on Tuesday. "It's throwing good money after bad. It's time for her to resign -- someone else to take charge."

    Sebelius is expected to testify again before the Senate Finance Committee on the rollout of ObamaCare, committee chairman Max Baucus, D-Mont., said in a statement. The hearing is scheduled for Nov. 6.