The Obama administration announced on Tuesday that more than 7 million Americans have enrolled in private health care plans through the Affordable Care Act over the last six months, meeting the administration’s goal for the program in 2014 and potentially resulting in a huge reduction in the number of uninsured Americans.

“With the remarkable surge in enrollment, 7,041,000 signed up for health insurance before the midnight deadline,” White House Press Secretary Jay Carney said Tuesday.

Only 4.2 million had enrolled through February, meaning that an aggressive effort by the White House and liberal groups succeeded in pushing almost 3 million Americans to sign up over the last month. It’s also likely that many Americans were motivated by the penalty for not getting health insurance under the law, which is $95 or 1 percent of a person’s income, whichever is higher.

White House aides have described reaching 7 million as a huge comeback from October and November, when only 365,000 Americans had enrolled amid widespread problems with the healthcare.gov website.

Republicans correctly note that some of these people have not yet paid for their plans, the final step in being enrolled.

And it’s likely that the administration fell short of another of its goals, making sure that about 40 percent of those enrolled were between ages 18 and 34. (Current estimates suggest that between 25 and 33 percent of new enrollments are young adults).

Month by month Obamacare enrollment numbers:
Oct: +106K
Nov (thru Nov 30): +259K (365K total)
Dec (thru Dec 28): +1.8M (2.2M total)
Jan (thru Feb 1): +1.15M (3.3M total)
Feb (thru March 1): +942K (4.2M total)
As of April 1: +2.8M (7M total and counting)

It remains unclear exactly how many of the estimated 47 million Americans who were previously uninsured now have health-care coverage. Some of the 7 million, as the White House has acknowledged, are people who had private insurance before and simply purchased plans through the new systems set up under the law.

At the same time, the subsidies under the law have likely helped millions who were uninsured obtain coverage they could not previously afford.

And the overall number of people who have health insurance through the Obamacare system is above 7 million, because that total does not include enrollments through Medicaid, people who signed up directly with an insurance company and adults between ages 18 and 26 who were able to remain on their parents’ plans because of the law.

Surveys and further analysis by both the federal government and non-partisan groups over the next few months are expected to more closely scrutinize these figures and provide a clearer picture of exactly what role Obamacare has played in its two main goals: expanding access to coverage and implementing systemic reforms to the health care system that drive down costs.

And the debate over the law is likely to continue. Democrats, including President Obama, are pushing hard for about two dozen states, nearly all of which either have a Republican governor or GOP-controlled state legislature, to expand their Medicaid programs to the majority of poor adults, as the law calls for.

Meanwhile, conservative-leaning health experts say that the estimated 10 million Americans who were eligible for subsidies under the law but chose not to enroll demonstrate that the ACA requires insurance plans that so comprehensive that they are too costly for people who are not worried about getting sick.

Perhaps most important will be how health insurance companies react to these first six months under the law. Although health-care experts say this is very unlikely, insurance companies could either choose not to participate in the law in the future or increase the costs of plans based on what they have learned since October.

“The real questions are: Are the premiums (net of the tax credits the government is providing) affordable to people? ” wrote Drew Altman, president of the non-partisan Kaiser Family Foundation, in a recent piece.

“Will they be stable or begin to spike in year two in some parts of the country if the risk pool is worse than insurers expected? Do people who get coverage under the law think it’s a good deal or not? Does enrollment ramp up as expected over time, decreasing the number of Americans uninsured? The current focus on national enrollment numbers and signups by young adults doesn’t tell us a great deal about the answers to these questions, and they are not a good metric by which to judge year one success.”

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