WASHINGTON — African-Americans in the South are shunning city life for the suburbs at the highest levels in decades, rapidly integrating large metropolitan areas that were historically divided between inner-city blacks and suburban whites.

Census figures also show that Hispanic population growth for the first time outpaced that of blacks and whites in most of the South, adding to the region's racial and ethnic mix.

"All of this will shake up the politics," said Lance deHaven-Smith, a political science professor at Florida State University in Tallahassee. Because the South is a critical region for Republicans in presidential elections, "all the Democrats have to do is pick up a couple Southern states, and Republicans are in trouble."

The share of blacks in large metropolitan areas who opted to live in the suburbs climbed to 58 percent in the South, compared to 41 percent for the rest of the U.S., according to census estimates. That's up from 52 percent in 2000 and represents the highest share of suburban blacks in the South since the Civil Rights Act passed in the 1960s.

The South also had major gains in neighborhood integration between blacks and whites. Thirty-three of the region's 38 largest metro areas made such gains since 2000, including all the large metros in Florida and Georgia, according to a commonly used demographic index. The measure, known as the segregation index, tracks the degree to which racial groups are evenly spread between neighborhoods.

Topping the list were rapidly diversifying metros in central Florida, as well in Texas and Kentucky, according to an analysis of 2010 census data released Thursday by William Frey, a demographer at the Brookings Institution. Black-white integration accelerated over the past decade in Atlanta, whose share of the black population declined from 61 percent to 53 percent.

The decline in Atlanta's black population is partly due to new suburban families including Ray Taylor, 34, and his wife, Marcia, 33. Four years ago, they moved from Atlanta to the northern suburb of Alpharetta, Ga., about 20 miles away, seeking better schools and a wider range of community activities. They now have two small children, ages 4 and 1.

Taylor, a political independent who voted for Democrat Barack Obama in 2008, said he liked having more exposure to people of different racial and political backgrounds. Compared with Atlanta, Alpharetta has a broader mix of whites and Hispanics and tends to lean more Republican.

"We wanted to be close enough to access the city and have the best of both worlds," he said.

Census figures also show that Hispanics contributed more to population gains than blacks in 13 of the 16 Southern states over the last decade, compared with seven states for Hispanics from 1990-2000. It was a clear sign of the shift under way for a region in which African-Americans have been the dominant minority group dating back to slavery.

In all, Hispanics accounted for roughly 45 percent of population gains in the South over the last decade, compared with about 22 percent for whites and 19 percent for blacks. Hispanic growth also has been surprisingly larger than expected in several Southern states, with official counts exceeding earlier estimates by more than 10 percent in Alabama, Louisiana and Maryland, according to the Pew Hispanic Center.

"It's clear that black growth continues to locate in the suburban South, leading to declines in their historic segregation," Frey said. "This new dispersed growth of blacks, coupled with the new waves of Hispanic growth, are changing the region's longstanding 'black-white' image and heralding the beginning of a more diverse region."

The latest race figures offer a hint of some of the coming political wrangling in fast-growing parts of the South, where Hispanic immigration as well as an influx of blacks from the North — two minority groups which tend to lean Democratic — have the potential to shift historic voting trends.

Next year, the South will be the site for the GOP National Convention in Tampa, Fla., and the Democratic National Convention in Charlotte, N.C., both states Obama carried in 2008 due partly to a large minority turnout. Both Charlotte and Tampa last year became cities in which whites now make up less than 50 percent of the population.

Other findings:

—In the South, white children in Florida, Georgia, Maryland and Mississippi became a numerical minority for the first time this past decade, joining Texas and the District of Columbia. In Florida, where Obama has often sought to highlight education initiatives, about 28 percent of children are Hispanic, 20 percent black, 3.2 percent multiracial and 2.4 percent Asian.

—Metropolitan areas in the South showing some of the biggest advances in black-white residential integration included Tampa, Orlando and Lakeland in central Florida; Louisville, Ky.; and Houston. Their segregation levels all fell in the middle range. Metro areas in the West also had substantial changes with generally lower levels of segregation, while segregation in the Midwest and Northeast declined somewhat but was typically higher than average.

—The South is the second most racially and ethnically diverse U.S. region after the West. Roughly 61 percent of its population is white, 19 percent black and 15 percent Hispanic. That's compared with a national breakdown of 65 percent white, roughly 12 percent black and 16 percent Hispanic.

—Hispanics in large metro areas in the South were more likely to live in suburbs — about 60 percent, compared with 56 percent for the rest of the nation.

DeHaven-Smith said the higher levels of black residential integration could make it harder for states to maintain majority black districts when they redraw political boundaries in the coming months. He also noted Florida's demographic changes, with the central part of the state now becoming a presidential battleground due to an influx of non-Cuban Hispanics who are turning the Republican-leaning area more Democratic.

Florida will pick up two new House seats — which means two more electoral college votes beginning in 2012 — based on its population growth over the last decade. Census figures released Thursday showed population gains over the last decade exceeded 30 percent in central Florida counties such as Osceola, Lake, Sumter, Hernando, Pasco and St. Lucie.

"It's a narrowly balanced, very polarized state, with the shifts occurring mostly in central Florida," deHaven-Smith said.