President Barack Obama's healthcare law is facing its biggest test this weekend since its disastrous October 1 launch, as Americans find out whether the administration has met a self-imposed deadline to fix its insurance shopping website.

Another major outage of glitch-ridden HealthCare.gov could spell more political trouble for the president, who was forced to apologize for the botched rollout and admit burdening Democratic Party allies in their bids for re-election to Congress in 2014.

If the website does not work on Saturday's deadline, that could turn off millions of uninsured Americans, especially young and healthy consumers whose participation in the new insurance exchanges are critical for keeping costs in check.

Democratic leaders in Congress might also find it necessary to extend open enrollment beyond the March 31 deadline and delay fines mandated by the law for people who do not have insurance by that date - a prospect that insurers warn would destabilize the market.

Obama officials are confident that this second coming of HealthCare.gov will be much improved from the October 1 debut. Millions of people looked into the website in its first month, but only about 27,000 cleared the gauntlet of technical obstacles to sign up for insurance.

The portal is the gateway for health insurance plans in 36 states under the Patient Protection and Affordable Care Act, commonly called Obamacare, which was passed in 2010. It is intended to move the United States closer to universal care by subsidizing insurance sold by the private sector for less affluent families.

Officials have said that by Saturday the website will be able to load quickly and work accurately for at least 80 percent of users. They have said it will be able to handle 50,000 simultaneous visitors, for a daily total of about 800,000, twice the capacity seen even on Wednesday before a final flurry of hardware and software fixes over the Thanksgiving holiday.

And officials have warned that the website will still suffer some delays and outages in the weeks to come. To help consumers left hanging when traffic exceeds capacity, they have created a new "queuing system" to tell consumers when to come back.

Short of a major outage, it may be difficult to immediately measure the administration's success because officials only release enrollment figures once a month. That will make anecdotes from consumers and enrollment groups all the more important.

"Even if it's working well, people will encounter problems," said Mark Hall, a Wake Forest University professor of law and public health. "You hope there's more good stories than bad stories."

Obama's approval rating drops

The abysmal launch of Obamacare has hurt the president and congressional Democrats, with Obama's approval ratings dipping to the lowest point of his presidency. A Reuters/Ipsos poll this week showed 56 percent of Americans disapprove of how Obama is doing his job, while 38 percent approve.

If the situation worsens, Democrats could risk losing control of the Senate in 2014, when 20 Democratic senators face reelection, and many are in tight races. Republicans have called for the law to be scrapped because they consider it an unwarranted expansion of the federal government and believe it will push up insurance costs.

Obama's chief of staff Denis McDonough now meets every other week with Democratic senators running in 2014 to reassure them Obamacare is on the mend, a White House official said.

The administration has prioritized fixes that consumers see, leaving other parts of the system for a later date. On Wednesday, officials said they would delay online enrollment for small businesses for a year.

Obama issued a rare apology earlier this month for mishaps with the rollout.

But as November 30 has drawn closer, Obama has become more assertive. "The website is continually working better, so check it out," Obama said in a speech on Tuesday.

Kathleen Sebelius, secretary of Health and Human Services, told a group of state and local officials on a call this week that "we are definitely on track to have a significantly different user experience by the end of this month."

Insurance companies have also noticed the difference.

"I don't expect this to be an overnight change because it appears they have been making improvements as they go," said J. Mario Molina, chief executive of Molina Healthcare Inc, a company offering plans in nine states, including California.

"It is easier to navigate. It's working better. It's faster," Molina said.

Even if the website does stand up to increased traffic, there are issues on the system's "back end" that need to be addressed.

As much as 30 to 40 percent of the site still needs to be built to handle payments and federal subsidies, a federal official told lawmakers earlier this month.

And the administration is planning a "soft launch" with small volumes for long-delayed Spanish language enrollment tools for more than 10 million uninsured Latino Americans.

Once the website is fixed, the White House also faces the challenge of raising awareness about the law. More than 35 percent of people without insurance say they have heard nothing about the new marketplace, according to polling by the Kaiser Family Foundation.