But the exchanges are set to become the primary path to coverage for people whose employers don't offer insurance.
Noncitizens are more likely to work in jobs and industries that don't offer coverage. They are far more likely to be uninsured.
And come 2014, when health coverage becomes mandatory, undocumented immigrants are expected to make up the lion's share of those who remain uninsured.
Low-income advocates say this could have serious public-health consequences for cities such as Los Angeles, where immigrants are almost as numerous as those who are native born.
That's true, too, for some neighborhoods in Utah.
"Whether they're here legally or not, do we really want to discourage them from paying for health care?" asks Lincoln Nehring, a health-policy analyst at Voices for Utah Children.
The new health law, however, diverts more funding to federal charitable clinics, which cater to undocumented immigrants. That, coupled with a projected drop in the uninsured, could free them to serve more of those in need.
"We see all uninsured. All we want to know is, do they live in community we serve and do they qualify as low income?" said Alan Pruhs, associate director of the Association for Utah Community Health.
And these clinics do it on the cheap.
"We can treat a patient three times a year for about $500, whereas one visit to the ER back in 2006 was more than $800," Pruhs said. "Having access to primary care keeps patients' chronic diseases controlled and costs in check you know, that hidden tax on all our insurance premiums."
The payoff is highest for pregnancies.
"We save the system a lot of money by providing good prenatal care and preventing moms from showing up at the ER and delivering a baby with serious complications. A baby in intensive care can be a million-dollar baby."