A key official in the repair effort for HealthCare.gov said the site's error rate is now lower than 1 percent thanks to weeks' worth of special improvements were made.
Former White House budget director Jeff Zients, who was enlisted to triage the website, touted the development as a sign of progress.
"It's likely that, as we move forward, we'll find additional glitches," Zients said on a call with reporters.
"Our bottom line continues to be that by the end of November, we will have the site working smoothly for the vast majority of users."
The administration is hoping to fix the site by Nov. 30, a self-imposed deadline designed to assuage criticism over the system's faulty launch.
The cut-off date has additional significance as millions of people receive notices that their insurance policies have been canceled.
The wave of notices has created a political firestorm for the White House, culminating in President Obama's announcement that insurers can continue to offer canceled plans for one year to people who previously had them.
In a bid to spurn the White House, the GOP-led House also voted Friday to allow insurers to sell canceled policies to any customer for one year.
A significantly improved ObamaCare enrollment site is seen as one development that could help turn the news in Obama's favor.
But many users are still facing serious problems with the system, casting doubt on how quickly the repair effort is moving.
Technicians working on the site are also facing headwinds as more and more people log in to purchase coverage.
Applicant numbers are expected to rise week on week until Dec. 15, the cut-off for people to enroll if they want plans that begin Jan. 1.
Zients said his next priority is adding capacity to the system, which is currently handling 20,000 to 25,000 users at one time.
He noted that there were no unscheduled outages on the site in the past week, a positive sign, and that more than 60 bugs were recently fixed.
The call was not fully positive, however, as Centers for Medicare and Medicaid Services spokeswoman Julie Bataille acknowledged that some insurers are still receiving flawed application data.
"We are actively working on with issuers ... to put that fix in place as soon as possible," Bataille said.