People sit with an insurance advisor as they sign up for the Affordable Care Act in 2015.

A record number of Americans signed up for Obamacare Thursday on what they thought would be the last day to enroll in health insurance coverage that starts in the new year, President Barack Obama said Friday.

So many people visited the federal government website that the administration extended the deadline until early next week to give more people time to sign up for what could be the last year of Obamacare coverage.

The Republicans who will control Congress and the White House starting next month say they'll repeal the law that provides the insurance markets as soon as they can — although there's no clear plan for how, when or what to put in its place.



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Obama plugged the health insurance marketplace, the centerpiece of the 2010 Affordable Care Act, in his last press conference of the year before heading to Hawaii for vacation.

"Yesterday was the biggest day ever for Healthcare.gov. More than 670,000 Americans signed up to get coverage," Obama said.



That's compared to 600,000 sign-ups last year on the Dec. 15 deadline.



@larry_levitt: Big ACA enrollment numbers are remarkable given the political noise, uncertainty about the future of the law, and lack of public attention.

Obama said when he took office, 44 million Americans lacked health insurance. "Today, we have covered more than 20 million of them," he said. "For the first time in history, more than 90 percent of Americans are insured."

Republican opponents of Obamacare don't dispute the coverage numbers but say the law has failed to bring down costs for consumers, as had been promised.



Premiums have risen as insurance companies taking part in the exchanges have struggled to make the profits they seek with the other restrictions imposed by the law. Obamacare limits the ability to charge higher premiums for women and older people, and it forces insurers to take all comers, even people who are already sick.

