Mainers seeking to sign up for health insurance through online marketplaces that launched Tuesday under Obamacare weren’t stalled by the government shutdown which is rooted in an impasse over the law in the nation’s capital. But technical glitches — along with the political infighting — tested consumers’ patience.

More than 1 million people visited Healthcare.gov, the federal government’s website for the new marketplaces, before 7 a.m., President Barack Obama said Tuesday in explaining the glitches, which prevented many people from enrolling.

Tuesday marked the opening of the health insurance marketplaces at the heart of the pivotal health reform, marking a major milestone for the Affordable Care Act even as it fueled a heated congressional standoff in Washington, D.C.

The shutdown won’t mean much for the marketplaces, which are funded with a pot of federal money that isn’t tied to yearly budget fights.

Dick Barclay of Holden said he visited the federal site early Tuesday morning only to receive a “try again later” message after spending 20 minutes setting up a username and password. He had hoped to shop for a health plan for his wife, who expects the premium for her existing policy to jump to at least $1,500 a month. He doesn’t think the Affordable Care Act will help them much.

“Like everything the government does, it is screwed up,” he wrote in an email. “I’m about done with this and am on the verge of not participating in this worthless program.”

Health care advocates urged consumers to stick with it, saying officials predicted opening-day bugs and stressing that individuals have six more months to sign up. Americans without health insurance have until the end of March to sign up in order to avoid tax penalties.

Consumers also may call for help, fill out paper applications, and visit in person with designated marketplace “navigators” and assisters.

Local health advocates said the high volume of Web traffic indicated great interest in the health insurance marketplaces, which consumers and small businesses can use to shop for private health plans.

Most Mainers receive health coverage through an employer or government programs such as Medicare and Medicaid and don’t need to worry about the marketplaces, which are designed to serve the uninsured and individuals who buy their own coverage. Only about 5 to 8 percent of Maine’s population is eligible to shop on the exchanges, according to the state insurance bureau.

Charlene Brousseau of Manchester was stymied in her attempts to log onto Healthcare.gov on Tuesday morning, but she remained optimistic. She said she expects to purchase a suitable health plan in the coming days with help from Consumers for Affordable Health Care, an Augusta advocacy group spreading the word about the marketplaces.

“I’m just trying to sort out all the different plans and what really fits best for me,” said Brousseau, who retired from a job in education after her husband suffered a stroke.

Brousseau, at 61, is four years away from qualifying for Medicare, the government health insurance program for the elderly and disabled. Until then, she’ll have to buy her own plan. But she expects to qualify for new federal subsidies and tax credits available under the law to help her afford health insurance.

Consumers can apply through the marketplaces for federal help to afford their coverage. While some states will operate the marketplaces themselves, Maine and 26 other states chose to let the federal government run them.

Small businesses with fewer than 50 workers also can shop on the marketplaces.

The health insurance plans come with new consumer protections, including a prohibition on insurers denying people with pre-existing health conditions and another that prevents companies from charging them more.

Despite an overloaded Healthcare.gov site, residents in some areas of Maine remained unaware of the outreach efforts. By mid-Tuesday morning, staff at the Aroostook County Action Program in Presque Isle had not received a single call about signing up through the marketplaces, according to Torry Eaton, ACAP senior manager in charge of employment and training programs. ACAP is one of several designated “navigators” around the state providing information and assistance with insurance options under the new law.

“We have not gotten any calls yet,” Eaton said. “Despite all the news and information out there, people don’t seem to know they can sign up for discounted insurance.”

Her office has received calls in recent days from residents who expressed concern over their future insurance status, she said.

“We are trying to get the word out that if you already have insurance that you are happy with, you don’t need to worry [and] you are all set,” Eaton said. “But if you have a bad plan or an unaffordable plan, you may want to switch.”

The Maine Lobstermen’s Association, another group informing Mainers about their health insurance options under the law, plans to conduct more outreach later this fall when the season slows down, according to Executive Director Patrice McCarron.

“Most guys are busy fishing,” she said in an email.

Bjorn Streubel, who is assisting people in Waldo County to navigate the health care marketplaces, said Waldo Community Action Partners’ office received about 20 calls Tuesday compared with 10 calls in the previous two weeks.

Some callers wanted assistance because they do not have computer access. Those that do were frustrated, he said, by the computer system being overwhelmed. Streubel said he advised people to be patient and not abandon the process of seeking insurance.

“My primary goal is to advise people to go slow and to take away the fear,” he said.

At a Portland marketplace kickoff event, Dr. Wendy Wolf, president and CEO of the Maine Health Access Foundation, said it will take time to get Mainers enrolled in health coverage.

“We won’t get everybody who’s uninsured enrolled in the first year,” she said. “I think we should be ambitious and [try to] get 20,000 or 30,000 people in the first year, but it’s a marathon, not a sprint.”

BDN writers Julia Bayly, Bill Trotter, Stephen Betts and Seth Koenig contributed to this report.