As political debate continues to rage over President Barack Obama’s signature health careoverhaul, the law already is reshaping health care in the most troubled communities in Chicago and its suburbs.

Since 2010, Illinois health clinics have received more than $50 million in development grants under the Affordable Care Act to build new facilities, expand operations, modernize equipment and improve the overall quality of care for the state’s poor and uninsured.

The money has sparked a building boom for health centers across the region and is ushering in a new era of competition to care for the growing pool of insured Americans. Supporters say this competition will drive down costs for patients and expand their options, allowing them to shop around for the best care and not just the most affordable.

But competition is a new challenge for small community health clinics that operate on shoestring budgets. As treating the poor becomes more profitable, bigger and better-funded medical centers are expected to seek a larger share of the marketplace.

“If the larger organizations decide they’re going hard after all those newly insured patients, you could see a feeding frenzy,” said Dr. Robert Winn, associate vice president for community-based practice at the University of Illinois Hospital & Health Sciences System. “I hope it doesn’t happen, but I’d be wary of it.”

On Chicago’s West Side, work crews this week continued to install the glass and metal exterior on a $44 million five-story clinic that will treat four times the number of patients seen at the university system’s current largest facility.

Six miles north, construction is winding down on a new 24-room health center with updated technology and even a rooftop garden. When it opens this fall, it will be the ninth clinic run by the nonprofit Near North Health Service Corp.

In Waukegan, on a commercial street lined with taquerias and other Latino-owned businesses, the Erie Family Health Center of Chicago is embarking on a $7 million renovation of a vacant bank building into a modern medical facility.

And on Chicago’s Far South Side, in the historic but blighted Pullman neighborhood, city officials recently joined employees of the Chicago Family Health Center at the opening of a sun-filled $10 million health clinic that triples the capacity of the cramped center it’s replacing.

Development grants alone aren’t enough to design, build and staff these projects. Some organizations obtained millions in private donations, secured loans or made use of city tax credits to see the projects to completion. But the federal grants jump-started the process, officials said, accelerating projects that may have taken years longer to get off the ground.

“Without those federal dollars, this doesn’t happen,” Winn said. “We’re talking about something that can transform the lives of thousands of people just in Chicago.”

Community health clinics have served the poor and uninsured for decades but became an especially vital component of the health care system during the prolonged recession. For as little as $15 a visit, patients in the Chicago area have access to primary care doctors, dentists, lab work, prenatal care and an array of other services.

Up to now, many of those patients have had no insurance. For example, more than half the 35,000 patients who sought medical care last year at one of Near North Health Service’s clinics were uninsured. At the nonprofit Lawndale Christian Health Center on the West Side, which serves a growing Hispanic community of low-wage workers, 35 percent of its patients are uninsured.

To care for everyone who walks in the door, the clinics rely greatly on reimbursements from the federal government for care provided to people covered by Medicaid or Medicare, plus some money from private insurers.

But the money coming in falls well short of what it actually costs to provide services, said Warren Brodine, CEO for the nonprofit Chicago Family Health Center, which served nearly 30,000 people last year on the city’s Far South and West sides. More than a third did not have health insurance.

The health care law is expected to bring big changes to community clinics, but no one is certain how they will play out. Perhaps, as patients gain insurance, clinics will see a surge of customers. But some officials suspect the opposite — that newly insured people will take advantage of the opportunity to consult other doctors who offer unique care or who are closer to home.

Officials say they simply cannot afford to lose those patients and still manage to provide affordable, quality care to those who still lack insurance, including noncitizens.

“We live on the margins,” said Iliana Mora, chief operating officer for the Erie Family Health Center. “We really do.”

For low-cost clinics accustomed to drawing patients from across the region, the financialstakes are high.

At the Lawndale Christian Health Center, for example, roughly 2,000 clients are now eligible for coverage thanks to the health law’s Medicaid expansion. That could bring in an additional $700,000 to $800,000 a year to the organization’s coffers, CEO Bruce Miller said. Across Illinois, the number of low-wage earners eligible for Medicaid will grow by about 342,000 this year.

Most clinics will use any extra money that comes in to reinvest in the product, adding more physicians, more support staff, more services, Miller said. But those improvements too will drive competition, he said.

“We’re constantly thinking about what we offer and what we can do better,” said Miller, whose health clinic added a full-scale fitness center and healthy eating cafe. “It’s competition, but ultimately we all want the same thing — for patients to get the best care they can.”

The Affordable Care Act, the majority of which kicks in Jan. 1, has allocated about $11 billion to improve care at community clinics in the U.S. over the next five years. Doctors say one goal is to bolster the nation’s ability to address the chronic health problems rampant in poor communities: obesity, diabetes, high blood pressure, heart disease.

If the law can remove the barriers that keep people from getting routine medical care, they say, it will lessen the need for urgent hospital or emergency room visits that burden the system.

“It’s all about preventive care and treating people before there’s an emergency,” Brodine said. “When you’re talking about hypertension, diabetes, by the time you’re feeling sick from it, the damage is done.”

Longtime Pullman resident Bonita Higgenbottom, 54, is already convinced of the benefits.

“There was a time where the only time I saw a doctor was in the emergency room,” she said on a recent day while waiting to get a checkup at Chicago Family Health Center’s new clinic on 115th Street. “Chest pains, bronchitis, high blood pressure, arthritis, hyperthyroid, you name it. I had a lot going on that I mostly chose to ignore.”

Higgenbottom said her attitude changed when she became eligible for Medicaid in 2009. Since then, she has made regular doctor visits to the Chicago Family Health Center clinic, sometimes taking two buses to get there when she cannot get a ride from a friend.

But as the law takes effect, how many previously uninsured patients will follow her example? That’s perhaps the biggest unknown facing health clinics, said the Rev. Randall Harris, board chairman of the University of Illinois Health’s Mile Square Health Center.

Harris, a pastor at Faith Community Church in the East Garfield Park neighborhood, said poor communities have much to gain from the health law, but it takes time to build trust. Whether they’re insured, people have to understand the need for regular checkups and see the value in building relationships with doctors, Harris said.

“I think people’s attitudes about going to the doctor will change; they have to change,” Harris said. “But it will take time. My hope is that our biggest challenge won’t be, ‘How do we get people in the door?’ but, ‘How do we respond to the demand?'”