There's nothing like a deadline to make people sign up for Obamacare.
More than 400,000 people enrolled in Obamacare insurance plans on the federal exchange HealthCare.gov during the week that ended Friday.
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The surge of sign-ups more than doubled the enrollment rate of recent weeks—and brings total enrollments on HealthCare.gov to more than 7.15 million people, according to data released Wednesday by the Health and Human Services Department.
Given the fact that HealthCare.gov serves just 37 states, that tally makes it even more likely that the Obama administration will easily hit its target of enrolling at least 9.1 million paying customers in Obamacare plans this year.
In fact, it's possible that number has already been exceeded nationally, as a result of sign-ups on the other Obamacare exchanges operated by individual states and the District of Columbia.
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There are no hard numbers on where enrollments currently stand officially on all of the exchanges. However, the enrollment tracking site ACASignups.net, which has a track record of making accurate sign-up predictions, was estimating that total national enrollment now stands at 9.5 million, after factoring in the new HealthCare.gov tally.
The site's operator, Charles Gaba, said that according to his analysis, 33 states have already reached the 2015 enrollment targets set by either HHS or the states running their own insurance marketplaces.
For enrollments to be considered official, customers must pay their first month's premiums.
Open enrollment in Obamacare plans began Nov. 15, and ends Feb. 15. Experts predict there will be a big wave of people signing up in advance of next month's deadline, particularly because they face a potential tax penalty if they fail to have some kind of health coverage by that date.
"Time is running out," said HHS Secretary Sylvia Burwell. "If you don't have health coverage, visit HealthCare.gov or contact the marketplace call center to learn about your options and financial help that is available."
Most applicants for coverage on HealthCare.gov qualify for some form of financial assistance with their monthly plan premiums. Such aid is available to people with low and moderate incomes.
People who lack health coverage in 2015 face fine that is equal to as much as 2 percent of their taxable household income.
Before the start of open enrollment this season, there were about 6.7 million people enrolled nationally as paying customers in Obamacare plans.