

A tea party member reaches for a pamphlet titled "The Impact of Obamacare", at a "Food for Free Minds Tea Party Rally" in Littleton, N.H. in this Oct. 27, 2012 file photo (Jessica Rinaldi/Reuters)

More than 6 million Americans have now signed up for private insurance under the Affordable Care Act, according to the White House, with just four days to go until the end of its first open enrollment period.

While traveling in Italy on Thursday, President Obama shared the news in a conference call with thousands of health-care navigators and volunteers helping enroll people on state and federal marketplaces.

As the volume of consumers seeking health plans has surged -- there were more than 1.5 million visits to HealthCare.gov Wednesday and more than 430,000 calls to the marketplaces' call centers -- Obama urged those on the call to work even harder to get individuals covered.

The numbers show that the administration will at least meet the expectations many have at this point, though it will fall short of the Congressional Budget Office's original enrollment projections. Last year the CBO estimated that 7 million consumers would sign up during the law's initial, six-month enrollment period; its most recent estimate projected 6 million would.

The actual enrollment number is likely to rise, in part because of recent changes to the law's implementation. The administration announced this week that it would extend the March 31 deadline into mid-April for those individuals who tried to enroll but failed to do so, and until the end of May for battered spouses who had previously been barred from receiving tax subsidies.

Across the country, several groups allied with the law -- including Enroll America, the Service Employees International Union and Planned Parenthood -- have been ramping up their enrollment activities as the deadline approaches. Nationwide, there are also more than 27,000 trained assisters in all 50 states helping consumers sign up under the law.

The Obama administration is courting a certain demographic as the enrollment deadline looms. So who’s on the receiving end of the last-minute hustle?