President Barack Obama has asked the U.S. Senate to confirm Andy Slavitt as the administrator of the Centers for Medicare & Medicaid Services (CMS).

Slavitt has been serving as acting administrator of CMS since Marilynn Tavenner stepped down from the role at the end of February. Slavitt joined the government in 2014, after working as an executive vice president at UnitedHealth Group's Optum unit, which helped fix the main Obamacare website, healthcare.gov. 

Slavitt faces some opposition, however. U.S. Senate Majority Leader Mitch McConnell (R-Ky.) issued a statement saying Slavitt's nomination would receive "thorough consideration" and advised Slavitt to remain focused on serving the 140 million Americans estimated by the CMS to receive insurance under its programs. 

“The head of the agency that oversees Medicare and Medicaid should be focused on what the American people expect him to do: administer these important programs, not allow his attention to be diverted instead to the implementation of some gigantic, unworkable healthcare law that hurts hardworking Americans,” McConnell said. “It has long been clear that no one can successfully manage a law as unworkable as Obamacare.”

Slavitt previously worked as group executive vice president of Optum, a unit of UnitedHealth Group. He was one of the executives helping with the so-called tech surge to fix HealthCare.gov in the months after it launched. He also served as CEO at UnitedHealth's Ingenix unit. It's that history that concerns

Senate Finance Committee Chairman Orrin Hatch (R-Utah) also issued a statement on the announcement, noting his concerns about Slavitt's "conflicted history in the medical services industry. Mr. Slavitt will need to answer a number of tough questions regarding his former employer and their relationship with the agency.” 

HHS has previously issued an ethics waiver for Slavitt, who will have to recuse himself from matters involving UnitedHealth, including contracts and analytics work from the Lewin Group, a UnitedHealth unit. UnitedHealth is the largest carrier of Medicare Advantage plans.