Almost 8.8 million people signed up as of last Saturday for insurance plans sold by the federal Obamacare health plan marketplace for 2017 coverage, officials announced Wednesday.

That tally compares to about 8.6 million plan selections on that HealthCare.gov exchange during the same time period for the prior open-enrollment season. HealthCare.gov serves customers in 39 states; the remaining are served by their own, state-run marketplaces.

"With 8.8 million Americans signed up for coverage through HealthCare.gov, more than last year at this time, it is clear that Americans want and need this vital coverage," said U.S. Department of Health and Human Services Secretary Sylvia Burwell.

"As we enter the New Year, Americans who are still uninsured should sign up by January 15th to have coverage starting February 1."

About 6.55 million of the plan selections were from returning customers. The remaining 2.2 million were from new HealthCare.gov customers.