AUGUSTA — Consumers signing up for health insurance on the marketplaces created under President Barack Obama’s landmark health care law have consistently turned to big-name insurers over smaller nonprofits and startups. But Maine has gone the other way, with a vast majority of residents putting their trust in the new co-op Maine Community Health Options over well-known Anthem Blue Cross and Blue Shield.

The co-op signed up nearly 20,000 of the Mainers who enrolled on the state’s federally run marketplace as of the beginning of March, or about 80 percent of the total in that time. Residents have been drawn to the co-op’s outreach efforts, nonprofit model and broad network of providers, experts say.

“The notion of the nonprofit appeals to people,” said Trish Riley, the former director of the Governor’s Office of Health Policy and Finance who helped craft Maine’s Dirigo Health Insurance Program, a subsidized program with similarities to the federal health care overhaul that was phased out at the end of the year. Thousands of Mainers who had plans under the program were forced to find new coverage, Riley said.

“They naturally turned to the co-op,” she said. “That makes us unique here.”

Ken Voorhees, 58, of Litchfield, said he chose the co-op in part because he liked that it’s locally owned and operated and he believes the profits will go toward improving his benefits.

“Some of the money is going to trickle down to the services that we receive,” said Voorhees, who operates a timber frames business.

The co-op is one of 23 that were created under the new law and loaned $2 billion to start up in order to spur competition on the marketplaces, also known as exchanges. But they’ve stumbled in many states, in part due to difficulties developing brand recognition, compounded by restrictions on lobbying and advertising that were conditions of accepting the loans.

Connecticut’s nonprofit grabbed only 3 percent of the people who enrolled on the exchange before the end of the open enrollment period on Monday. Similarly, in Maryland, the co-op signed up only about 650 people through early March.

In Maine, the co-op’s efforts to sign up customers began months ago with outreach and marketing funded in part by a $300,000 grant from the board of the Maine Health Access Foundation. The co-op reached out to communities that weren’t being targeted by other insurers or brokers, said Wendy Wolf, president and CEO of the foundation.

“It’s almost like no group was too small,” she said. “They really tried to lay the foundation with groups who were sort of on the margins of getting good benefits.”

Anthem Blue Cross Blue Shield declined to provide its enrollment numbers but said it’s received an increase in applications for plans both on and off the exchange over the past week. Rory Sheehan, a spokesman for the insurer, said its plans were developed with “an eye toward continued long-term sustainability and they reflect our long-term commitment to the success on the Affordable Care Act.”

Kevin Lewis, CEO of Maine’s co-op, said he believes that residents embrace the company’s plan design, which encourages consumers to address small health problems early before they turn into more serious — and expensive — conditions. Among other things, the company provides lower out-of-pocket costs for medication and office visits for people with asthma and diabetes in the hopes of reducing ER visits down the line.

“What’s contributing to our enrollment numbers is certainly our ability to deliver a value both on price and the benefit design,” Lewis said.

Others in the health care industry point to op Maine Community Health Options’ broad provider network as contributing to attractiveness to customers.

The nonprofit’s network extends to every hospital in the state, and even some in New Hampshire, while Anthem’s network excludes six Maine hospitals.

Anthem said the narrow network allowed it to offer insurance premiums that cost 8 percent less than if it had crafted a broader network, but experts say the prices offered by two companies are comparable.

“Given that (Anthem) had a tighter network and high prices, it just wasn’t that compelling,” said Riley, who chose the co-op for her own health insurance policy.

Associated Press writer Susan Haigh in Hartford, Conn., contributed.

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