Kennedy, a 70-year-old environmental activist who has spread misinformation on vaccines, was questioned last week by both Republican and Democrat senators on the Senate's Finance and Health committees. The Finance Committee will vote this week on whether to push Kennedy's nomination to a full Senate vote.
Groups that oppose Kennedy's confirmation see a handful of Republican senators as potential swing votes against Kennedy, including Sen. Bill Cassidy, R-La., and Sen. Mitch McConnell, R-Ky.
If confirmed, Kennedy would run HHS, which oversees more than $3 trillion in healthcare spending, including at the Food and Drug Administration and the agency in charge of the Medicare and Medicaid health insurance programs covering nearly half of all Americans.