For five years, Tara Carino lived with the knowledge that she could soon die, and there was nothing she could do about it.

A lump near Carino’s groin slowly ballooned to the size of a baseball, eventually becoming so painful she could barely walk. But as a cancer survivor, the mother of four found herself rejected again and again by insurers who considered her too sick and costly to insure — leaving her unable to see a doctor.

That all changed on Jan. 1 of this year. The Woodstock mom is one of nearly 317,000 Georgians who signed up for health coverage on the federal Health Insurance Marketplace. Such successes notwithstanding, Obamacare opponents maintain that the law is too intrusive and is driving up costs for everyone.

The marketplace started its second open enrollment period this weekend after last year’s disastrous launch, which featured near-daily website crashes and glitches that prevented people from completing applications.

U.S. Department of Health and Human Services Secretary Sylvia Burwell said Friday that the department had performed extensive load testing — that is, the number of people who can use the site at any one time — in advance of Saturday’s launch.

“We think we’re going to have a better experience than last year during this open enrollment,” Burwell told Telemundo Atlanta. “We do know that, like any website, there will be some downtime. But we’ve also put in place testing so that we know when that does happen, we very quickly understand what’s gone wrong, make sure we’re communicating and get it fixed quickly.”

Although critics predicted the early demise of the federal marketplace, experts say it appears to be working the way it was intended.

One of the biggest concerns early on was that too many sick and costly Americans would sign up, driving up premiums without enough younger and healthier individuals to offset the increase.

“That’s not what we’re seeing,” said Christine Eibner, a health policy expert with RAND Corp., a research organization. “It doesn’t look like we’ve seen evidence of the death spiral (some people) predicted.”

Indeed, in Georgia, the marketplace’s second full year of operation brings with it four new private insurers, a variety of new health plans and lower premiums in some cases. All bode well, experts say, for the marketplace’s long-term stability.

Bill Custer, a health insurance expert at Georgia State University, estimates another 150,000 to 200,000 Georgians could buy marketplace plans for 2015.

“The insurers themselves perceive a sustainable and workable market,” he said.

Latest legal challenge could change the game

But what success the marketplace has achieved could soon be shattered.

Next year, the Affordable Care Act will face its biggest challenge since the Supreme Court upheld the law in a landmark decision in 2012.

The justices agreed nine days ago to hear an appeal that, like that earlier case, has the potential to bring down Obamacare. The central issue is the tax credit most people receive when they buy policies on the Health Insurance Marketplace; the vast majority of Americans — including 87 percent of Georgians — will receive the credit for 2014, making their new insurance affordable.

In King v. Burwell, however, the plaintiffs assert that those tax breaks are illegal in dozens of states. (The details: the tax credits are OK in states that created their own online insurance marketplaces, according to the plaintiffs; they claim the tax credits are illegal in states that opt to use the federal marketplace, as Georgia does.)

“Obamacare is doing real harm to American families. It’s driving up out-of-pocket costs for families, narrowing access to choices, and taxing innovation,” Georgia Congressman Tom Price said in a statement following the court’s announcement that it would hear King. “But there’s also a larger principle under threat here, which is the rule of law in this country.”

Without those tax credits, millions of Americans may not be able to afford their coverage and would drop it, destabilizing the marketplace.

It would also reduce the incentives for younger, healthier people to buy coverage, which would lead to higher premiums for everyone, Custer said.

‘Giving you an insurance card but not health care’

Critics of the law also point to the Obama administration’s recent enrollment estimate — 9.1 million by the end of 2015 — as proof that the marketplace and law as a whole are in trouble. The Congressional Budget Office initially estimated that roughly 13 million Americans would be signed up by next year.

Many who do have marketplace plans, meanwhile, face higher premiums, said Ron Bachman, a senior fellow at the Georgia Public Policy Foundation, an Atlanta-based think tank focused on market-oriented proposals. Bachman pointed to a study by consulting firm McKinsey & Co. that predicted gross premiums would increase for most 2014 marketplace plans. In Georgia, some premiums for 2015 went down, while many rose modestly, the latest state data shows.

Many marketplace plans also have narrow networks with fewer health care providers to choose from, which can hurt access to care, Bachman said.

“They’re giving you an insurance card but not health care,” he said. “The networks are so narrow that you can’t get care.”

The narrow networks issue will remain a challenge, experts say. If insurers cut down on the doctors and hospitals in their networks, they are able to funnel more patients to the doctors and hospitals that remain. These providers, in turn, are willing to accept lower rates from the insurer in exchange for the greater number of patients.

“‘It’s a balance between access and affordability,” said Morgan Kendrick, president of Blue Cross and Blue Shield of Georgia, which has added 1,200 doctors to its networks this year.

Lymph node ‘just got bigger and bigger’

Carino, a self-employed public relations and crisis management specialist, pays $110 a month for her marketplace plan. But that cost would be roughly $510 without her tax credit — a price Carino doubts she could afford, especially with four kids.

Her plan was one of the pricier marketplace plans Kaiser Permanente offered, but with a history of cancer, Carino knew she’d need it.

She made a doctor’s appointment immediately after the insurance kicked in last January.

By that time, Carino struggled just to get out of bed because the lymph node had become so swollen and painful. Eventually, she was diagnosed with clear cell sarcoma, a rare and often deadly form of cancer.

“It just got bigger and bigger,” she said. “It was so big, you could literally see it through my clothes.”

Surgery to remove the lump and a cancer diagnosis soon followed. Carino said she couldn’t have afforded the procedure without insurance. She had been willing to pay for it, but before the Affordable Care Act, insurers just refused to sell it to her.

“It’s not that I wanted to be on welfare,” she said. “That was the most disparaging thing.”

‘Cost and affordability are what it’s all about’

The Supreme Court isn’t expected to rule on the contentious tax credit issue until the summer.

In the meantime, insurers, health care providers and consumer advocates are focused on reaching as many uninsured Americans as possible in the next three months of open enrollment. That’s half the length of time people had to select coverage last year.

Staff at Atlanta Medical Center downtown have already attended more than 20 events to get the word out about the marketplace. The hospital also has eight counselors who can help guide consumers through HealthCare.gov.

The fact that more people now know about the marketplace and are familiar with it should help enrollment efforts, said hospital CEO Thomas Casaday.

“Now that a handful of people are enrolled and had good experiences, I think it provides a sounding board to assure friends you’re not putting yourself at risk,” he said.

Casaday said he couldn’t predict whether the marketplace will be sustainable, but he said it’s helpful in efforts to make sure more people get insurance.

Regardless of whether the federal marketplace survives long-term, the idea of an online marketplace that provides transparency on prices is here to stay, said Graham Thompson, head of the Georgia Association of Health Plans.

“(Insurers) are committed to transparency. We’re aggressively trying to make people aware of their choices,” Thompson said. “Cost and affordability are what it’s all about.”

Constant fear of death finally receding

Carino had the surgery to remove the cancerous lymph node earlier this year and now, according to her doctors, appears to be cancer-free.

The Affordable Care Act, Carino says, saved her life. She’s no longer swallowed by fears that any day she could die.

Her good fortune and new lease on life have inspired Carino to begin working with a nonprofit to help clean up an area of downtown Atlanta where she sees people who are destitute, who are hungry, who have nowhere to live.

“I lived so long just existing — thinking I was going to die,” she said. “Now, I want to live and give other people hope.”