Non-Hispanic whites now make up two-thirds of the total U.S. population, the bureau said, but that proportion will dip to one-half by 2050, according to the agency's latest projections.

In a new report, estimating population levels as of July 1, 2004, the Census Bureau said Texas had a minority population of 11.3 million, accounting for 50.2 percent of its total population of 22.5 million. Texas is the fourth state in which minority groups, taken together, account for a majority of the population. But no one racial or ethnic group by itself accounts for a majority of the total population there.

Steven Murdock, the state demographer for Texas, said, "In some sense, Texas is a preview of what the nation will become in the long run."

"Our future in Texas is increasingly tied to our minority populations," Murdock said. If their education and skills continue to lag, he added, the state will be less competitive in the global economy.

Members of racial and ethnic minorities also make up more than half the population in Hawaii (77 percent) and New Mexico (56.5 percent).

In California, state officials said minorities had accounted for more than half of the population since 1998, and the Census Bureau said they now made up 55.5 percent of the total. Minorities accounted for about 40 percent of the population in each of five other states: Maryland, Mississippi, Georgia, New York and Arizona.

New York had the largest black population, 3.5 million, while California had the largest Hispanic population (12.4 million) and the largest Asian population (4.8 million).

Murdock said immigration accounted for half of the recent increase in Texas' minority population, while the excess of births over deaths accounted for the other half. Hispanic women, who are having children at a rate of three per woman, had a significantly higher fertility rate than blacks, with an average of 2.3, and non-Hispanic whites, with an average of 1.9, Murdock said.

In the four-year interval from the last census, in April 2000 to July 2004, the bureau reported, the total population of the United States grew 4.3 percent, to 293.7 million, and the black population increased by 5.7 percent, to 39.2 million. But, it said, the Asian population increased 16.2 percent, to 14 million, and the Hispanic population rose 17 percent, to 41.3 million. Hispanics can be of any race.

In the same four-year period, the bureau said, the non-Hispanic white population grew 1.1 percent, to 197.8 million, while the rest of the nation - the "minority population" - grew 11.6 percent, to 95.8 million.

Cecilia Munoz, a vice president of the National Council of La Raza, a Latino civil rights group, said: "This great diversity and constant demographic change make us a dynamic country. They do not cause unrest or commotion. They are part of a process that's intrinsically American."

Munoz said "the political strength of Latinos takes a while to catch up with our demographic strength," in part because one-third of the Latino population is under the age of 18 and many Hispanics are not citizens.

Among counties, the Census Bureau said, Los Angeles had the largest Hispanic population, 4.6 million, and the largest Asian population, 1.4 million. Non-Hispanic whites accounted for just 30 percent of the county's total population of 9.9 million.

Cook County, Illinois, which includes Chicago, had the largest black population, 1.4 million.

The Census Bureau data show that Hispanics account for 36 percent of the total population in the nation's five largest counties: 9.1 million of the 25.4 million people who live in Los Angeles; Cook County; Harris County, Texas (Houston); Maricopa County, Arizona (Phoenix); and Orange County, California.

In Texas, as in many other states, said Murdock, a professor at the University of Texas, San Antonio, "the white population is growing very slowly, while other racial and ethnic groups are growing quite rapidly."

Officials in California and Texas said Hispanics had fanned out across their states, while the black population tended to be more concentrated in urban areas.

Hispanics are the largest ethnic group in four of the five largest cities in Texas, Houston, Dallas, San Antonio and El Paso, according to Murdock. But, he said, they also accounted for much of the population growth in rural counties.