WASHINGTON (AP) — It's getting harder to sign up the uninsured for health coverage.

The Obama administration says it expects only slight coverage gains next year for the health care law's online insurance markets.

On Thursday, the Department of Health and Human Services announced a target of 10 million people enrolled and paying their premiums by the end of 2016. This year's goal was 9.1 million paying customers, and the administration has said it's on track to meet that.

The health care law has reduced the share of Americans without coverage to historic lows by offering a combination of subsidized private insurance and expanded Medicaid.

But officials say finding new private insurance customers is getting harder, partly because the most eager ones have already enrolled. The new sign-up season starts Nov. 1.