Obamacare is now the 2 million person plan.
At least 2,016,387 people have enrolled nationally in private insurance plans sold through federal and state-run health exchanges as of Monday, an analysis of official and unofficial data by CNBC.com has revealed.
While that number is well below the 3.3 million people federal officials last fall projected would be signed up by Dec. 31, it represents a strong rebound from the dramatically low level of enrollments seen in October and most of November, which reflected the serious technological problems on the federal HealthCare.gov exchange and several state exchanges.
And experts Monday said that with three more full months of open enrollment in Obamacare insurance left to go, millions more will likely sign up, possibly enough to top the 7 million total sign-ups that officials had projected last fall before the HealthCare.gov launch debacle.
Connecticut's exchange crowed Monday about becoming the first exchange to outpace original projections for its enrollments.
(Read more: "Direct" online enrollment in Obamacare stymied )
"CMS [Centers for Medicare & Medicaid Services] projected that Connecticut would enroll a total of 33,000 consumers by the end of the enrollment period. As of December 23rd, there were 34,295 Connecticut consumers enrolled in private plans through Access Health CT," said Kevin Counihan, CEO of Access Health CT, the state's exchange.
"This is a tremendous accomplishment; however, our work is far from done. We will continue working to provide even more consumers with access to quality, more affordable health-care coverage through the duration of open enrollment," Counihan said.
"I wouldn't be surprised if we exceed 7 million [nationally] by March," said Timothy Jost, a law professor who specializes in health-care legal issues at the Washington and Lee University School of Law. "I'm encouraged by the fact that we've got close to 2 million people signed up [officially] and in time we're going to get a lot more people signed up by March 31."
Jost noted that major national and state-based ad campaigns by supporters of the Affordable Care Act, which were supposed to launch in the fall, were suspended because the problems on HealthCare.gov made it unwise to encourage people to go to a website that was effectively not working.
With the resolution of much of the tech troubles on HealthCare.gov-which sells Obamacare insurance in 36 states-"there's going to be a very aggressive effort to get people to sign up" beginning in January, Jost said.
On Sunday, the head of the CMS announced that "more than 1.1 million people enrolled in a qualified health plan" on HealthCare.gov "from Oct. 1 to Dec. 24."
"More than 975,000 of those enrolling" did so in December, noted the official, Marilyn Tavenner, administrator of the CMS. "December enrollment so far is over seven times that of October and November."
By adding HealthCare.gov's announced enrollment to the officially reported tally of 797,530 sign-ups on the 15 health exchanges run by the remaining states and the District of Columbia, the officially announced tally is just below 1.9 million.
But a dramatic surge of enrollments in California and several other states in recent weeks, the most recent numbers not yet reflected in the official data, brings the true tally to what is likely to be at least 2.016 million as of Monday.
That surge came with the approach of deadlines for enrolling in coverage that begins Jan. 1.
"Everyone said all along that people were going to wait until the last month to enroll," said Washington and Lee's Jost.
But he added that a "big problem is that we just don't have any idea how many people would have enrolled if people could have enrolled in the first two months."
"The numbers tell us that the website [HealthCare.gov] didn't work for the first two months," Jost said.
Jonathan Wu, chief analyst at the consumer finance website ValuePenguin.com, said the 2 million enrollment benchmark is "pretty good considering how many problems they had, considering they lost almost two months of enrollment."
"They should be pretty pleased," Wu said.
But now, Wu said, the "tricky part" is continuing what has become a relatively strong pace of enrollments into the first quarter of 2014.
"At this point," Wu said, "anybody who really needs insurance has probably gotten it."
(Read more: California's in a Golden State with Obamacare )
"Now you have to convince the rest of the people why this is a good deal for you," he said. "I think the heaviest list is people who didn't have insurance before, and didn't see the need for insurance."
Many such people will be younger, less-affluent adults, whose tight budgets and relative good health will make buying insurance less of a pressing need, Wu said.
"My concern is whether younger people will find this to be a really good deal or not," he said.
Most adult Americans who don't have health insurance in 2014 through either their employer, the Obamacare exchanges or government health programs like Medicare and Medicaid, are subject to a tax penalty of $95 or 1 percent of their income, whichever is higher.
Wu said it remains an open question for younger adults whether that penalty, known as the individual mandate, will be "enough to push them into the market" and buy insurance they didn't previously have.
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