A wave of immigration, the aging of non-Hispanic white women beyond child-bearing years and a new baby boom are diminishing the proportion of children who are white. Already, half of U.S. children younger than 1 are Hispanic, black, Asian, Native American or of mixed races.

"A lot of people think demographics alone will bring about change and it won't," said Gail Christopher, who heads the W.K. Kellogg Foundation's America Healing project on racial equity. "If attitudes and behaviors don't change, demographics will just mean we'll have a majority population that is low-income, improperly educated, disproportionately incarcerated with greater health disparities."

In 2010, 39.4 percent of black children, 34 percent of Hispanic children and 38 percent of American Indian and Alaska Native children lived in poverty, defined as an annual income of $22,113 that year for a family of four. That compares with about 18 percent of white, non-Hispanic children, according to Census Bureau's 2011 American Community Survey.

Asian children overall fare better, with 13.5 percent living in poverty, the survey said.

The overrepresentation of minority children among the poor is not new. What is new is that minority children will, in the not-too-distant future, form the core of the nation's workforce, and their taxes will be depended on to keep solvent entitlement programs for the elderly.

Based on where things stand for nonwhite children today, it's not hard to make some educated guesses about what the future holds for the youngest of America's children who already are a majority of their age group, said Sam Fulwood III, a senior fellow at the Center for American Progress.

The recent recession worsened conditions for many children, but minorities were hard hit and are having more difficulty recovering.

The Pew Charitable Trusts found that, from 1999 to 2009, 23 percent of black families and 27 percent of Hispanic families experienced long-term unemployment, compared with 11 percent of white families. Pew Research Center, a subsidiary, found that the median wealth of white households is 20 times that of black households and 18 times that of Hispanic households.

That means more minority families end up in poor neighborhoods with underperforming school systems, leading to lower graduation rates and lower lifetime earnings, said Leonard Greenhalgh, a professor of management at Tuck School of Business at Dartmouth College in New Hampshire.

"You are looking at the future workforce of the United States — what we need to be competitive against rival economies such as India and China, and we are not educating the largest, fastest growing percentage of the U.S. workforce, so as a nation we lose competitive advantage," Greenhalgh said.

It all starts with preschool, where overall enrollment has been increasing but Hispanic children are less likely to be included. Of Hispanic children ages 3 to 5 in the U.S., 13.4 percent were enrolled in full-day public or private nursery school in 2011, according to data from the National Center for Education Statistics.

That compares with 25.8 percent of black children enrolled in full-day preschool and 18.1 percent of white children. But already, Hispanics are one-quarter of students enrolled in public schools.

The situation prompted San Antonio Mayor Julian Castro to push for voter approval to raise the sales tax and expand preschool opportunities in his city, which is 63.2 percent Hispanic.

"I see a gap in educational achievement for San Antonio children versus children in Texas and the nation, and a large percentage of those are minority children and of course, we wanted to change that trajectory," Castro said in an interview.

President Barack Obama has proposed raising cigarette taxes to help pay for preschools. He has proposed a program to entice states to expand preschool programs to reach families with incomes up to twice the poverty line, and to require full-day kindergarten. But the partisan political showdown over government spending and raising taxes has led to across-the-board federal spending cuts and stalls in other legislation that may delay those proposals.

Sheila Smith, early childhood director at Columbia University's National Center for Children in Poverty, points to years of research that show kindergarteners perform better if they received high-quality early care, and if teachers used specific strategies aimed at developing behavior and language and math skills.

"If you have minority children from low-income families in very enriched preschool settings … we see they make very big gains," Smith said. "But how many classrooms are very enriched to the point that we see kids making these very big gains? Not nearly enough."

Compounding the issue, experts say, is immigration status. About 4.5 million children of all races born in the U.S. have at least one parent not legally in the U.S., according to the Pew Hispanic Center. More than two-thirds of impoverished Latino children are the children of at least one immigrant parent, the center reported.

Latino and Asian immigrants over past two decades are driving a significant portion of the demographic change, and ensuring their children can succeed is critical, said Brookings Institution demographer William Frey.

"They're the future of our labor force. They're the future of our economy," Frey said. "They're the people who white baby boomers are going to have to depend on for their Social Security, for their Medicare and just for a productive economy to keep all of us going in the future."

The picture isn't all bleak. History and recent data show improvements for the next generations of immigrant families.

The Pew Research Center found second-generation Americans, some 20 million U.S.-born children of 20th century immigrants, are better off than their immigrant parents. They have higher incomes, more graduate from college and are homeowners and fewer live in poverty, the study found.

Many experts on low-income children see good health as one more building block for education and prosperity. Children are less likely to learn if they are ill and missing school and unable to see a doctor.

On a recent weekday, 9-month-old Anderson sat on his mother's lap in the waiting room of the clinic at Mary's Center, a community organization in the nation's capital. He had struggled for three days with diarrhea, cold symptoms and vomiting.

He and his two siblings are American citizens, but their father and mother, Alba, who did not want her last names revealed because neither parent is in the country legally, are not. The children's health care is covered by Medicaid, and Alba says she wants them to be healthy so they can have a better life. "They have to go to college," said Alba, originally from El Salvador. "They have to do better, since their mother can't."

Anderson's generation will be the first to fully grow up under the new federal health insurance mandate taking effect next year. The act requires free preventive services and also extends money for the Children's Health Insurance Program through 2015.

In 2011, about 94 percent of black children, 92.3 percent of Asian/Native Hawaiian and Pacific Islander children and 95 percent of white children had health insurance coverage, while 87.2 percent of Hispanic children and 83.4 percent of American Indian and Alaska Native children had some form of health insurance coverage, according to a study by Georgetown University's Center for Children and Families.

The numbers of uninsured children are at a historic low — just 7.5 percent, said Joan Alker, the center's executive director.

While 73.1 percent of white children had private coverage, more than half of black and Hispanic children got health care through Medicaid and the Children's Health Insurance Programs and similar federal and state subsidized programs, the Federal Interagency Forum on Child and Family Statistics reported.

"We have the increasing rates of childhood asthma, childhood obesity and these are going to lead to problems later in life, so it's far better to make sure those kids have health insurance so you can address those issues as much as possible now," Alker said.