Washington (CNN) -- President Barack Obama announced Friday that he will nominate Sylvia Mathews Burwell, who currently directs the White House budget office, to be the next health secretary, the Cabinet official who's ultimately responsible for overseeing Obamacare.
Obama praised the outgoing secretary, Kathleen Sebelius, saying at a Rose Garden ceremony that she would "go down in history" for serving when the United States "finally declared that quality, affordable health care" would be a right for every U.S. citizen.
"I will miss her advice. I will miss her friendship," Obama said. "I will miss her wit."
Her departure is not without controversy although her tenure will conclude more positively with the Obama administration riding high over the initial enrollment success of the politically charged health law.
Obama acknowledged the early problems with the government's HealthCare.gov website last fall, which was an enormously tumultuous period for Sebelius.
But Obama followed up by saying that "her team" turned the corner and "got it fixed, got the job done" in carrying out the sign-up period from October through March. "The final score speaks for itself," Obama said with 7.5 million people signed up for health coverage.
The Affordable Care Act, Obama's signature domestic achievement, aims to provide insurance for millions of Americans without it.
Burwell is also no stranger to making tough calls.
As director of the Office of Management and Budget for the past year, Burwell was at the center of last fall's budget drama during which she was responsible for sending out the shutdown order for federal agencies.
During the ceremony, Obama touted Burwell skills as someone who can handle tough challenges.
"Sylvia is a proven manager, and she knows how to deliver results," he said. "And she'll need to be a proven manager because these are tough tasks, big challenges."
She also has a history in Washington circles that extends beyond her current position. She was a budget and campaign official for Bill Clinton.
At the Department of Health and Human Services, she inherits an agency heavily criticized for implementing the health law.
Sebelius' tenure coincided with passage of the 2010 law with no Republican support. The political turmoil around its passage and its rocky rollout has become a rallying cry for the GOP heading into next fall's midterms where control of the Senate is at stake.
But the website's performance did improve significantly as the year turned, quieting early calls from Republicans for her to step down.
This month, in a letter to department employees, Sebelius reflected on Obamacare sign ups exceeding its target of 7 million as evidence of "the progress we've made, together," while stating that "our work is far from over."
"I know that this law has been at the center of much debate and discourse in Washington, but what this enrollment demonstrates is that the Affordable Care Act is working and much needed," she said in the note.
Burwell, 48, has already been through Senate confirmation for her job at the White House, but will need to go through that again for the health appointment. Her nomination will likely face tough questions from Republicans.
"You can expect a robust discussion, both at the hearing and on the floor, on Obamacare and its consequences," said Don Stewart, a spokesman for Senate Minority Leader Mitch McConnell.
She came to the White House from her spot atop the Walmart Foundation, the giant retail chain's charitable organization that, according to its website, donated nearly $1 billion to causes worldwide in 2011.
Before that, Burwell worked for the Bill and Melinda Gates Foundation. In the Clinton administration, she worked under then-Treasury Secretary Robert Rubin.
CNN's Jim Acosta and Ted Barrett contributed to this report.