The Obama administration says more than 5 million people have signed up for private health insurance under the new health care law.

That still leaves about 1 million to go over the next two weeks for the White House to meet its latest goal of 6 million enrolled by March 31.

That would work out to more than 70,000 people a day. And some independent analysts say that's a stretch.

Medicare administrator Marilyn Tavenner announced the 5-million milestone in a blog post Monday.

March 31 is the last day to enroll for a taxpayer-subsidized health plan through the new online markets, or exchanges.

It's still unclear whether the White House will grant an additional grace period for people who've started—but not finished—their applications by that date.