WASHINGTON (AP) The nation's largest minority group risks being left behind by President Barack Obama's health care overhaul.

Hispanics account for about one-third of the nation's uninsured, but they seem to be staying on the on the sidelines as the White House races to meet a goal of 6 million sign-ups by March 31.

Latinos are "not at the table," says Jane Delgado, president of the National Alliance for Hispanic Health, a nonpartisan advocacy network. "We are not going to be able to enroll at the levels we should be enrolling at."

That's a loss both for Latinos who are trying to put down middle-class roots and for the Obama administration, experts say.

Hispanics who remain uninsured could face fines, not to mention exposing their families to high medical bills from accidents or unforeseen illness. And the government won't get the full advantage of a group that's largely young and healthy, helping keep premiums low in the new insurance markets.

"The enrollment rate for Hispanic-Americans seems to be very low, and I would be really concerned about that," says Brookings Institution health policy expert Mark McClellan. "It is a large population that has a lot to gain ... but they don't seem to be taking advantage." McClellan oversaw the rollout of Medicare's prescription drug benefit for President George W. Bush.

The Obama administration says it has no statistics on the race and ethnicity of those signing up in the insurance exchanges, markets that offer subsidized private coverage in every state. Consumers provide those details voluntarily, so federal officials say any tally would be incomplete and possibly misleading.

But concern is showing through, and it's coming from the highest levels.

"You don't punish me by not signing up for health care," Obama told Hispanic audiences during a recent televised town hall. "You're punishing yourself or your family."

Like a candidate hunting for votes in the closing days of a campaign, Obama was back on Hispanic airwaves Monday as Univision Radio broadcast his latest pitch.

Read more:

Latinos Being Left Behind In Health Care Overhaul