The 2012 battle for the ’burbs

In the past two presidential elections, almost two-thirds of the popular vote came from nation's 100 biggest metro areas. Each of these county clusters begins with a large urban core and extends across suburban counties with strong economic ties. In 2004 and 2008, Republicans won the least-settled suburban counties, while Democrats took the most urban ones. In between, the mature suburbs were a shifting battleground. They went for George W. Bush in 2004, but Barack Obama in 2008. The mature suburbs alone may not decide the 2012 presidential race, but they offer a geographic window on the swing voters who will. Will they stick with Obama? Or shift to presumed Republican nominee Mitt Romney? By Ted Mellnik, Laura Stanton and Karen Yourish

Battle in the mature suburbs map

County groups are based on census data released in March on people living in densely developed urban areas. City/high density: 132 counties - at least 95 percent of population in urban areas. Mature suburbs: 164 counties - 75 to 95 percent urban. Emerging suburbs: 186 counties - 25 to 75 percent urban. Exurbs: 91 counties - less than 25 percent urban.
SOURCES: U.S. Census Bureau, Brookings Institution, National Atlas of the United States - The Washington Post. Published May 8, 2012.