A big surge of consumers this fall is pushing up enrollment in health coverage offered through the Affordable Care Act, providing an unexpected boost to insurance marketplaces created by the law, according to new data from the federal government.
Through this week, nearly 6 million people have selected health plans for 2016 through HealthCare.gov, the federally operated insurance marketplace that serves residents of 38 states, including Florida, Texas and Illinois.
"The more who sign up, the stronger the system becomes," President Obama told reporters at the White House. "That is good news for every American who no longer has to worry about being just one illness or accident away from financial hardship."
Hundreds of thousands of additional consumers have selected plans through marketplaces operated by the remaining states, including California, New York, Connecticut and Maryland.
The strong demand for Obamacare coverage in the law's third enrollment period may further solidify the markets, which are still evolving as insurance companies and consumers continue to adapt to the new healthcare environment.
And it could help further drive down the nations' uninsured rate, which has plummeted since the health law's coverage expansion began in 2014.
Polls and other surveys indicate some 17 million previously uninsured Americans have gotten coverage through marketplaces, Medicaid and other sources.
The new surge also comes as the law's defenders face renewed attacks amid the exit of several new insurers from marketplaces around the country and the recent budget deal that will delay several funding sources in the law.
"The marketplace is demonstrating not only growth, but that it remains vibrant and strong," said Kevin Counihan, who oversees the markets at the Department of Health and Human Services. "That is a very important sign for the road ahead."
Federal officials were particularly heartened by the number of consumers coming to HealthCare.gov who did not have marketplace coverage in 2015.
Thus far, 2.4 million of the nearly 6 million HealthCare.gov enrollees have been new to the marketplace, more than a third more than signed up at this point last year, according to HHS officials.
Sign-ups from new consumers were even stronger this week, as millions of Americans rushed to reach a deadline to sign up for coverage to begin Jan. 1.
Overall, enrollment through HealthCare.gov is nearly twice what it was at this point last year, not counting consumers who will be automatically renewed by the end of this month.
The law allows Americans who don't get health benefits at work to shop among plans on state-based marketplaces operated by the federal government or by the states themselves.
Consumers making less than four times the federal poverty level – about $47,000 for a single adult or $97,000 for a family of four -- qualify for subsidies.
Insurers must provide a basic set of benefits and cannot turn away consumers, even if they are sick.
Federal officials had been expecting only modest enrollment growth in the markets in 2016, projecting that only about 10 million people would have coverage through the marketplaces by the end of next year.
That's only a small increase over 2015, when 9.1 million Americans are expected to have coverage through the marketplaces by the end of this year, according to HHS estimates.
And in recent weeks, insurers and the industry's Washington lobbying arm, America's Health Insurance Plans, have become increasingly vocal over their concerns about the marketplaces and the lack of healthier enrollees to balance out the sick consumers who are signing up for coverage.
AHIP spokeswoman Clare Krusing sounded a note of caution Friday about the latest sign-ups. "National enrollment figures tell one part of the story," she said. "To keep coverage affordable and ensure stability, there needs to be a balanced risk pool in local markets."
The open enrollment period runs through the end of January, but if consumers wanted coverage starting Jan. 1, they had to sign up this week.
As that deadline approached, federal call centers and HealthCare.gov were swamped with millions of consumers.
On Monday and Tuesday alone, call centers fielded more than 2 million calls and more than 3.7 million people visited the website, according to HHS officials.
That meant that an average of 11 consumers were signing up every second, officials said.
"It's clear now that many people have been waiting to purchase coverage until this enrollment cycle and coming back now," said Centers for Medicare and Medicaid Services administrator Andy Slavitt, whose agency operates the marketplace.
It is unclear what is driving the new surge in enrollment.
But federal officials speculated that consumers' ability to find affordable options in the marketplaces, particularly with subsidies, is playing a role.
HealthCare.gov and many state marketplaces also feature new tools this year that make it easier for consumers to compare plans, look at physician directories and estimate total costs, including premiums and out-of-pocket expenses such as co-pays and deductibles.
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