The Iowa Electorate

In 2012, Mr. Santorum found success in the northwest corner of the state where voters are more likely to be older and evangelical. Mrs. Clinton and Mr. Edwards won parts of the rural south in 2008, which is a mix of Democratic and Republican-leaning counties. Mr. Romney and Mr. Obama won counties in the urban centers in 2012 and 2008 respectively, where voters tend to be higher-earning, more educated and more racially diverse.