The Census Bureau and state Commerce Department estimated in 2009 that about 31 percent of the state's residents were Hispanic, so it is likely the recession and the state's crackdown on illegal immigration led some to leave the state.

The estimates were off by the most in the state's major urban areas of Pima, Pinal and Maricopa counties, said longtime Arizona State University economics and demographer researcher Tom Rex.

"There's lots of things that may have caused all that, but clearly the thought was how much of the influx of Hispanics was into the major urban areas," Rex said. "Therefore it would make sense that the combination of the recession and the employers sanctions law bear that out."

The state's white, non-Hispanic population as a proportion of the total population fell to less than 58 percent from nearly 64 percent in 2000. The number of whites grew by more than 420,000, from 3.27 million to 3.69 million, but that population's 13 percent growth rate failed to keep up with the surge in Latinos.

The Census Bureau counted 6.39 million Arizonans last year, up from 5.13 million in 2000. That put Arizona in the No. 2 spot in the nation for growth, behind Nevada.

"I think that the pattern that we're seeing across the country is consistent in Arizona," said Arturo Vargas, executive director for the National Association of Latino Elected and Appointed Officials. "If not the majority, certainly the most significant share of the state's population growth itself is due to the increase of its Hispanic population.

"In Arizona for example, Latinos accounted for nearly half of that state's overall population increase."

Just as important is the percentage of people under 18 who are Hispanic, Vargas said. In Arizona, it's 43 percent; in Texas, 48 percent; and in California, 51 percent of the young people are of Hispanic origin.

That's a cautionary tale for Arizona politicians who are pushing crackdowns on illegal immigrants, Vargas said.

"I think it's reasonable to assume that the anti-immigrant, which many Latinos perceive as anti-Latino, sentiment, is having an effect on Arizona's children," he said. "I think that probably will affect their views on their political participation when they then 18."

Arizona's accelerated growth rate slowed with the mid-decade housing crisis, but the state still grew faster than any other except Nevada.

The new census figures show Pinal was Arizona's fastest-growing county between 2000 and 2010, with the town of Maricopa leading with a giant 4,000 percent population increase.

Maricopa, about 40 miles south of Phoenix, was a crossroads farming town of just 1,040 residents in 2000. It exploded to 43,482 as it became a poster child for suburban growth.

The phenomenal growth in small towns that were on the outskirts of suburban Phoenix a decade ago was not unexpected. But the sheer numbers surprised even demographers who were expecting big increases.

Other top cities or towns for percentage gains were Surprise with 281 percent and Buckeye with 678 percent.

Pinal County grew by 109 percent, from 179,727 to 375,770. Other counties that showed large growth were Mohave with 29 percent and Yavapai with 26 percent, Maricopa with 24 percent and Santa Cruz with 23.6 percent.

Tiny Greenlee in southeastern Arizona was the only county to lose residents. It went from 8,547 to 8,437.