Jonathan Alcorn/Reuters - People gather for information during a Planned Parenthood Affordable Care Act outreach event for the Latino community Saturday in Los Angeles.

The Obama administration announced Monday that more than 5 million people have signed up for new insurance plans under the health-care law, suggesting new momentum for the program as the deadline to get covered this year approaches.

About 800,000 people selected health plans on the state and federal insurance marketplaces in the beginning of March, officials said in a blog post -- almost as many as signed up during the entire month of February. The figure brings the administration closer to Congressional Budget Office projections that 6 million people would enroll by the end of March.

Officials had predicted that the pace of enrollments would pick up this month, because March 31 is the last day to sign up for a marketplace plan and avoid a fine. The health law requires most Americans to have health insurance or incur a penalty of $95 or 1 percent of their income this year, whichever is higher.

The Congressional Budget Office had initially projected that 7 million people would sign up for new health plans by the end of March. Analysts revised that estimate last month, after it became clear that enrollment would be depressed by the technical difficulties on and a number of state-based insurance Web sites.

"The last several days have been the busiest since December," Marilyn Tavenner, administrator of the Medicare office, said in the blog post, noting that the federal hotline took 198,000 calls on Thursday alone. More than 4 million people visited last week, and another million logged on over the weekend.

"With only two weeks to go, we’re continuing to work hard to ensure that every American who wants to enroll in affordable coverage by the deadline of March 31st is able to do so," Tavenner wrote.

The White House and HHS have not said how many of those who have enrolled have actually paid their initial premiums.