HCR Update from Mark Sanna: More than 975,000 people signed up for health insurance through the federal exchange between Dec. 1 and Dec. 24, the deadline to enrollment to be covered by Jan. 1, the administrator for the Centers for Medicare and Medicaid Services said in a blog item posted today. Marilynn Tavenner, the CMS administrator, wrote that 1.1 million Americans have enrolled in insurance through the exchange since it opened Oct. 1.