Obamacare is now the 2.1 million person plan as the new Affordable Care Act health insurance plans selected by those people kick in for the first time on New Year's Day.
"Tomorrow is New Year's Day, and it's a new day for health care for millions of Americans," said US Health and Human Services Secretary Kathleen Sebelius on Tuesday as she announced that more than 2.1 million people had enrolled in private Obamacare insurance exchanges as of last Saturday.
But officials said they do not know what percentage of those people have actually paid their first premiums for the new plans, which is required to actually be enrolled. In many cases, those premiums are not due until Jan. 10.
Sebelius also noted that another 3.9 million people have been deemed eligible for the government-run Medicaid program via those federally and state-run Obamacare marketplaces by the end of November, the last reporting period for that data.
And she said HHS was committed to getting even more people signed up since "we're just halfway through a six-month open enrollment period."
"For many of the newly insured — people like Molly from Charlottesville, Va., Mark from Austin, TX — it will be the first time that they can enjoy the security that comes with health coverage," Sebelius said.
Sebelius announcement came a day after CNBC.com revealed the 2-million enrollment plateau had been topped. About half of the enrollments, or at least selection of plans without a premium being paid, came on HealthCare.gov, the federally run Obamacare insurance exchange that sells plans in 36 states.
In addition to clearly being pleased to report that millions of people have been enrolled — three months after the botched launch of HealthCare.gov — Sebelius underscored the fact that the plans those people selected, along with effectively all other insurance plans in 2014, will have new standards mandated by the ACA.
Those standards include no pricing discrimination against women or for people with pre-existing conditions, and mandated coverage without co-payments or deductible payments for things including preventative care.
"Starting tomorrow, being a woman will no longer be a 'pre-existing condition,' " said Sebelius.
Although the 2.1 million or more enrolled 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.
Experts 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.
(Read more: "Direct" online enrollment in Obamacare stymied)