Demographers say births to minorities could surpass the number of births to whites this year. The reason is an increase in Hispanic women of childbearing age immigrating to the U.S.

Hispanic women have an average of 2.9 children and whites have an average of 1.8.

In 2008, 48 percent of children born in the U.S. were minorities.

Whites currently make up two-thirds of the U.S. population, but census projections suggest minorities could be the majority by mid-century.

"Census projections suggest America may become a minority-majority country by the middle of the century. For America's children, the future is now," said Kenneth Johnson, a sociology professor at the University of New Hampshire who researched many of the racial trends in a paper being released Wednesday.

According to the study, about 1 in 10 of the nation's 3,142 counties already have minority populations larger than 50 percent. But 1 in 4 communities have more minority children than white children, or are close to that point.