WASHINGTON — Marilyn B. Tavenner, the former Obama administration official in charge of the rollout of HealthCare.gov, was chosen on Wednesday to be the top lobbyist for the nation’s health insurance industry.
Ms. Tavenner, who stepped down from her federal job in February, will become president and chief executive of America’s Health Insurance Plans, the trade group whose members include Aetna, Anthem, Humana, Kaiser Permanente and many Blue Cross and Blue Shield companies.
As the new voice for insurers, Ms. Tavenner will lead the industry in a time of tumultuous changes and challenges, including delicate negotiations with Congress over the future of the Affordable Care Act.
On Aug. 24, she will succeed Karen M. Ignagni, a former health policy specialist at the A.F.L.-C.I.O., who has led the industry’s lobbying arm for 22 years.
The board of America’s Health Insurance Plans unanimously elected Ms. Tavenner at a meeting here on Wednesday, according to Mark B. Ganz, the board chairman, who is also the chief executive of Cambia Health Solutions, based in Portland, Ore.
“This is a great opportunity,” Ms. Tavenner, 64, said in an interview. “AHIP has a longstanding reputation as focused on consumers and consumer advocacy, and being a leader in the transformation of health care.”
Most recently, Ms. Tavenner was the administrator of the Centers for Medicare and Medicaid Services, the federal agency that insures one in three Americans and has an annual budget of more than $800 billion. As administrator, she was in charge of HealthCare.gov.
She said that, because of federal conflict-of-interest rules, she would not lobby the agency or other parts of the Department of Health and Human Services in the remaining months of the Obama administration. But she said she was free to lobby Congress.
Mr. Ganz said that Ms. Tavenner had “the trust and respect of members of Congress from both sides of the aisle.”
Senator John Barrasso, Republican of Wyoming, described the selection in more negative terms. “While millions of Americans are still being hurt by Obamacare’s soaring costs and fewer choices,” he said, “Ms. Tavenner’s appointment shows how the law has created a cozy and profitable relationship for some.”
Another Republican senator, Bill Cassidy of Louisiana, said he admired Ms. Tavenner’s past work to help low-income older people eligible for Medicare and Medicaid.
Ms. Tavenner led federal efforts to carry out the Affordable Care Act. She was stunned in October 2013 when HealthCare.gov crashed, creating a political crisis for President Obama and frustrating millions of consumers who tried to buy insurance online.
In the ensuing months, she helped fix the website, after the White House deployed a management expert to supervise the operation, with the aid of technology experts from Silicon Valley.
“The rollout was far from ideal,” Ms. Tavenner said on Wednesday. “But I spent a month pulling a team together and creating a turnaround. The management challenges seemed insurmountable, but I am proud of what we accomplished.” Millions of people eventually gained insurance, she said.
Her selection as chief lobbyist for the industry highlights how federal health programs have become a priority for insurers, which increasingly depend on revenues from Medicare and Medicaid and the new public insurance marketplaces.
Ms. Tavenner, a nurse, worked for more than two decades at the Hospital Corporation of America, a commercial hospital chain. From 2006 to 2010, she was the secretary of health and human resources in Virginia, managing Medicaid and other programs.
Asked about her priorities, Ms. Tavenner said she wanted to protect Medicare Advantage, the program under which private insurers manage care for more than 30 percent of the 55 million beneficiaries of Medicare.
She also said she wanted to keep down the rising cost of prescription drugs. Ms. Tavenner’s move comes as some of the nation’s largest insurance companies pursue mergers. Aetna said this month that it would acquire Humana, and Anthem has made offers to acquire Cigna.
In September, Ms. Ignagni will become president of EmblemHealth, the parent of Group Health Incorporated and the HIP Health Plan of New York, which serve three million people.