Maisha Challenger never thought she’d have to set foot in a community health center. “I have been working my whole life so I usually am used to going to a doctor’s office,” she said.

But after she lost her job as an education lobbyist – and the health insurance that came with it – she had no choice. She enrolled in the DC Healthcare Alliance – a program in the District that provides free health care for people who don’t have insurance and don’t qualify for Medicaid or Medicare. Shortly after, she went to the Walker-Jones Health Center in Northeast Washington, D.C., for regular medical care.

Community Health Centers like Walker-Jones are federally funded and, though they see patients from all walks of life, their focus is on the millions of people who are uninsured or underinsured. More than 1,200 of these facilities operate in the United States, serving about 18 million people annually. But these centers – part of the health care safety net – are now being stretched thin. An estimated 6 million Americans are newly uninsured as a result of the economy’s downturn, according to the Kaiser Family Foundation. Overall, the number of people in the U.S. without health insurance is about 45 million.

Congress provided federally qualified health centers with $2 billion in the American Recovery and Reinvestment Act, the stimulus package signed into law in February. The cash infusion was designed to help these facilities accommodate the scores of people, just like Challenger, suddenly without health coverage but in need of care. Some experts, President Obama among them, view these centers as important players in the nation’s health care system. These facilities, they say, help fill a gap in the provision of primary and preventive health services. As a result, the stimulus package investment is considered by many to be a sign of things to come as health reform takes shape.

The clinics fill “an urgent need and this is a need that is going to continue well into health reform,” said Professor Sara Rosenbaum, chair of the department of health policy at The George Washington University in Washington, D.C.

But Joel Miller, senior vice president of operations for the National Coalition on Health Care, said he wasn’t convinced the centers can be part of a lasting health care solution. The Coalition is a nonpartisan alliance of health care organizations working toward health care reform.

“I’m just afraid that they’re not going to have the necessary funding long term [or] the kind of providers long-term to provide access for these populations,” Miller said. The stimulus funds are only guaranteed for two years, according to Department of Health and Human Services. He prefers fixing the system in a way that would enable every American access to a his or her physician.

But as these debates continue, CHCs are simply attempting to meet the needs of a growing patient base.

In 2008, Walker-Jones served 5,000 people. Projections for 2009 are at least double that number. In the first three months of the year, the clinic has treated more than 3,100 patients.

“Our enrollment has definitely increased over the last two months,” said Troy Martin, who manages the Walker-Jones Health Center. He expects even higher volume in the near future. “I realize it’s going to be a big spike because of the recession – because of people losing jobs.”

That’s where the stimulus funding comes in.

During the next two years, the federal government hopes to use these centers to expand health care to an estimated three million more people without insurance – a 16 percent increase. In March, the first payment – more than $500 million – was released. This money will lead to hiring or saving the positions of as many as 6,400 doctors, nurses and other staff. It also could be used to build as many as 126 new clinics.

Unity Health Centers, the umbrella nonprofit organization that supports Walker-Jones and 30 other Washington-area facilities, will receive a total of $900,000 from this allocation. But strings are attached. The money must be used within two years to create jobs, and clinics must report within 90 days regarding how they plan to spend it.

Unity CEO Vincent Keane said the money will help him hire more than 17 employees across his centers, including a new physician. He also plans to expand clinic hours.

“There’s a heavy emphasis on making sure the money gets out quick,” he said. “We will be actually required by July 1 to give a fairly comprehensive report.”

But implementing this plan is proving harder than he expected. One of the tests he has encountered is finding physicians who want to work in a community health center environment.

“It’s challenging,” Keane said. “We’re trying to do more in retention.”

Often, doctors don’t see working in a clinic as part of their career path, said Kurt Mosley, vice president of business operations for Staff Care and Merritt, Hawkins & Associates, both of which recruit physicians to fill temporary and permanent positions at hospitals and community health centers.

Such hiring challenges have become more pronounced as the nation’s supply of primary care physicians has diminished. And real-life evidence of how the physician deficiency could impact future expansions in safety net care can be seen by examining how clinics have fared in another locale, Massachusetts.

In 2006, that state required health coverage for all residents. Since that mandate – the first of its kind in the U.S. – more than 430,000 more residents have become covered.

Take the Lynn Community Health Center near Boston, where staff has simply run out of space for new patients – after seeing more than 30,800 patients last year and 28,500 in 2007. Lori Abrams Berry, the center’s executive director, said she couldn’t attribute the increase directly to the Massachusetts mandate that every person have health insurance because many other factors have contributed, too, including a phyisican shortage, an aging populations and growing unemployment.

“We have grown every year and the economy may have as much of an impact,” Abrams Berry said. “We’ll continue to grow, except that we don’t have anymore space.”

For the time being, she added, “the stimulus money specifically going to community health centers is designed to keep us alive and well so that we can be part of the solution to the problems of access and problems of cost.”

Overall, though, the discussion of funding issues and reform ideas ultimately feeds into a central theme that plays out across the nation: that many Americans continue to be without insurance and rely on the safety net for their access to care.

Melissa Pullins is one of them. She lives in Washington, D.C., on a fixed income, is unemployed and is not eligible for Medicare or Medicaid.

Since 2005, she’s been a regular at the Walker-Jones Clinic, where she has received the medication and ongoing specialty care she needs to manage her diabetes and its complications.

“Nobody knows when that day will come that you will be handed a pink slip,” Pullins said one day in April after a doctor’s appointment. “And if you don’t have employer-paid health care, clinics like Walker Jones become critical.”