Another 2.7 million are enrolled in plans through state-run marketplaces.

Read: Brokers and agents: Don't feel left out by PPACA

In a statement, Secretary of Health and Human Services Sylvia Burwell framed the enrollment as evidence that the PPACA system was strengthening by attracting healthier enrollees who will hopefully defray the costs of the older, sicker members that insurers have insurers say have made it tough for them to turn a profit on the exchanges.

“We’re seeing unprecedented demand for Marketplace coverage with more than 11.3 million people signed up for coverage,” she said in a department press release. “We’re encouraged that Marketplace consumers are increasingly young, engaged and shopping for the best plan. We have more work to do before the next deadlines and our focus continues to be the consumer experience and educating consumers about available financial assistance and their choices.”

According to the data, 4 million of the enrollees are under 35.

An administrator for the Centers for Medicare and Medicaid Services told the Washington Post that people in that age range represent 41 percent of new enrollees, up from 38 percent last year.

Not a dramatic difference, perhaps, but hopefully a marginal difference that can help shore up the finances of insurers struggling to cover the claims of older enrollees.