The government says these efforts have resulted is significant improvements:
- System speed has increased dramatically, with average response times of less than one second, down from more than eight seconds in late October.
- Error rates, on average, have tumbled from more than 6 percent to three-quarters of 1 percent.
- The system is now available more than 90 percent of the time, versus 42.9 percent in early November.
- The site can now support 50,000 simultaneous users -- up from 25,000 just days ago -- and can accommodate more than 800,000 users per day.
Even with these enhancements, there will be times "when spikes in user volume outstrip the system's capacity," Zients said. A new system will be deployed to allow consumers to request e-mail notification of better times to use the site, he said.
The Obama administration has been under fire in recent weeks as consumers seeking health insurance through the federal health marketplace have encountered numerous snags. A raft of error messages, timed-out web pages and slow response times gummed up the process and, many times, the site was inoperable.
Under the Affordable Care Act, most Americans must have health insurance in place by Jan. 1, 2014, or pay federal tax penalties.
Consumers seeking to purchase private health insurance through the federal health exchange must do so by Dec. 23 if they want that coverage to kick in on Jan. 1.
In the week leading up to the government's self-imposed Nov. 30 deadline for making the site work "smoothly" for the "vast majority" of users, the Obama administration conceded that the system would not operate perfectly on Dec. 1.
"It is likely as we move forward we'll experience additional glitches," Bataille said during a Nov. 25 news conference.
Even Sunday, one significant problem remained that the government has yet to fully resolve. The government's website is not always accurately transferring enrollment data to health insurers. Failure to accurately transfer those so-called 834 forms to insurers means a consumer who signs up for coverage may get lost in the system.
"Until the enrollment process is working from end-to-end, many consumers will not be able to enroll in coverage," Karen Ignagni, president and CEO of America's Health Insurance Plans, said in a statement issued Friday.