JUDY WOODRUFF: The woman who will likely be the new face of the health care law testified today on Capitol Hill. Sylvia Mathews Burwell, the president's budget director, is Mr. Obama's nominee to replace Kathleen Sebelius as secretary of health and human services.

Rarely is anything on Affordable Care Act a bipartisan affair anymore in Congress, but Burwell was well-received by members on both sides of the aisle.

SEN. LAMAR ALEXANDER, R, Tenn.: Ms. Burwell, you have a reputation for competence. And I would respectfully suggest you're going to need it.

HARI SREENIVASAN: That warning notwithstanding, Republicans, like Lamar Alexander, mostly used the hearing to take aim not at Burwell, but at the health care law.

SEN. LAMAR ALEXANDER: Republicans would like to repair the damage that Obamacare has done. We'd like to prevent future damage as responsibly and rapidly as we can.

HARI SREENIVASAN: But Burwell didn't concede that point. Instead, in her opening statement, she argued the effects of the law have been positive.

SYLVIA MATHEWS BURWELL, Director, Office of Management and Budget: The department's work to ensure accessible, affordable, quality health care through the implementation of the Affordable Care Act is making a difference in the lives of our families and our communities, while strengthening the economy.

HARI SREENIVASAN: If confirmed, Burwell would succeed Kathleen Sebelius, who announced her resignation last month. Republicans roundly criticized her for the botched rollout of the federal online insurance exchange last fall.

Today, South Carolina Republican Tim Scott pressed Burwell on whether she'd be an independent voice.

SEN. TIM SCOTT, R, S.C.: I would ask you simply, as secretary of HHS, will you in fact be the health and human services secretary for the American people, or will you be, as your predecessor has been, the ambassador of Obamacare?

SYLVIA MATHEWS BURWELL: I'm here to serve the American people. I'm part of the president's administration. I'm honored to be appointed. First and foremost, I serve the American people. I believe that the president and his policies are aligned with that and will work. But I am here to serve the American people.

HARI SREENIVASAN: That line of questioning drew a strong rebuke from Iowa Democrat Tom Harkin, the chair of the committee.

SEN. TOM HARKIN, D, Chair, Health, Education, Labor and Pensions Committee: It is my — my opinion, based upon the years of work with Kathleen Sebelius, Secretary Sebelius, that she performed her job admirably, and that she was a responsible and attentive secretary of health and human services, and carried out the law as we wrote it.

HARI SREENIVASAN: Democrats also touted benefits of the law, and Connecticut's Chris Murphy zeroed in on Republican governors who've balked at embracing key provisions, such as expanding Medicaid.

SEN. CHRIS MURPHY, D, Conn.: What are the ways in which we can work in a flexible manner with these states as they maybe wake up to the reality of how well the implementation is going after the initial botched rollout? What are the ways in which we can work with some of the states that haven't done things like Connecticut to try to make this work in all 50 states, rather than just in the handful that have set up their own exchanges?

SYLVIA MATHEWS BURWELL: I think there are two things, and it does come back to the point about flexibility, is one of the points. And I think what's important is to send a signal that folks are willing to have the conversations.

As I said, it's important, if there are fundamental principles, to articulate those in terms of the change you're trying to get, but be willing to have the conversations and hear the ideas.

HARI SREENIVASAN: Burwell's answers generally seemed to go down well. Some Republicans even spoke of her reputation for competence.

Before taking over at the Office of Management and Budget, she held leadership positions with the Wal-Mart Foundation and the Gates Foundation. She also served in the Clinton administration at the National Economic Council.

Richard Burr of North Carolina cited that background, saying he plans to support the nomination.

SEN. RICHARD BURR, R, N.C.: It's because she doesn't come with a single experience that would make her a good secretary. She comes with a portfolio of experience that would make her a tremendous asset at addressing some of the challenges that that agency specific — that agency specifically and uniquely has.

HARI SREENIVASAN: Burwell also got an outside boost, when America's Health Insurance Plans, an industry trade group, issued a statement calling her uniquely qualified. She still faces a separate confirmation hearing before the Senate Finance Committee. That hearing has not yet been scheduled.

GWEN IFILL: The reporter on that story, of course, was Hari Sreenivasan.

As rocky as the rollout of healthcare.gov has been, a new report says the federal exchange was a bargain compared to the state-run marketplaces, which spent twice as much per enrollee. That story is on our Rundown.