Republican-leaning states all across the South and West will gain congressional seats based on the results of the 2010 Census, according to population counts released Tuesday, a shift that will likely result in a change of strategy by political groups hoping to maximize in 2012.

The Census Bureau announced that eight states will gain a total of 12 seats, while 10 states -- mostly in the Northeast and Midwest -- will lose seats. The population shift sets the stage for potential GOP gains in Congress in 2012, while changing the political landscape ahead of a presidential race which in some respects is already starting.

"The 2010 Census will serve as a backbone for our political and economic system for years to come," Commerce Secretary Gary Locke said.

The Census Bureau unveiled the first package of results from the 2010 head count during a press conference in Washington. Director Robert Groves used the ceremony to announce the official U.S. population count as of April 2010 -- 308,745,538. The number marks a 9.7 percent increase from a decade earlier, a slower growth rate than recorded in previous counts. The population in 2000 was 281.4 million.

But the regional population shifts are what matter to lawmakers looking to boost their party's numbers in Washington. The Census is used to shape state legislative seats and allocate the 435 seats in the U.S. House of Representatives. With growth in the South and West averaging about 14 percent, states in those regions are set to gain the most additional representation in Congress.

Texas, continuing seven consecutive decades of growth, will gain the most seats with four more House members in 2012. Florida gains two, while Arizona, Georgia, Nevada, South Carolina, Utah and Washington each gain one.

States losing seats include Illinois, Iowa, Louisiana, Massachusetts, Michigan, Missouri, New Jersey, New York, Ohio and Pennsylvania. All those states lost one seat apiece, save for New York and Ohio, which lost two each.

Rep. Patrick McHenry, R-N.C., ranking member of the House Subcommittee on Information Policy, Census and National Archives, congratulated the Census Bureau for the work it did putting together the decennial count, and suggested the migration patterns show the Rust Belt is losing out to the Sun Belt because of better state and local opportunities.

"It is no coincidence that the states gaining population the fastest over the last 10 years have lower tax rates and, consequently, stronger economies. As states draw new congressional districts to reflect this shift, we will certainly see more Republicans in the U.S. House," McHenry said.

The shift of seats out of Ohio and into Florida, both legendary swing states, means the Sunshine State could take on a bigger role as a presidential battleground in 2012. States that gain more seats will be worth more in the Electoral College -- meaning presidential candidates from both parties may be spending more time in the South and West than they did in the last election.

The Census numbers are also used to allocate billions in federal aid. Locke added that businesses can use the information to figure out where they want to invest.