By Salena Zito

The political parties have a problem with white middle-class voters. Both major parties failed to connect with them in last month's presidential election.

Many pundits have pointed to high turnout among minorities and young people as the key to Obama's victory. But Sean Trende, a RealClearPolitics analyst, points to a factor that flew under the radar: White voters did not turn out, and they did not turn out in significant numbers.

Trende estimates that on Election Day, about 91.6 million votes were cast by whites, 16.6 million by blacks, 12.7 million by Latinos, and 6.3 million by other groups. Compare this with 2008, when there were 98.6 million white voters, 16.3 million blacks, 11 million Latinos, and 5.9 million from other groups.

Trende estimates that "the African American vote only increased by about 300,000 votes, or 0.2 percent, from 2008 to 2012. The Latino vote increased by a healthier 1.7 million votes, while the 'other' category increased by about 470,000 votes." What stands out to Trende is the decline in the number of whites voting for both parties.

Lara Brown, an expert on the Electoral College, believes Democrats have a problem with middle-class whites showing up in weak numbers, while Republicans have a problem with whites just not showing up. "The real difference between those voters is what their jobs are," she explained. "Democrats have a problem with blue-collar workers, and Republicans are having a problem with more rural voters, like farmers."

A University of Virginia Center for Politics analysis outlines the loss of the blue-collar segment of the Democrats' coalition in the part of Appalachia stretching south from New York, including chunks of the Rust Belt that were once significant sources of votes for Democratic presidential candidates. The analysis shows Southern Democrats Jimmy Carter and Bill Clinton fared well in that area. Carter won more than two-thirds of those 428 Appalachian counties in 1976, and Clinton won close to half. Obama won only 7 percent of them last month, and he lost every county in West Virginia.

Romney's white problem was nowhere more glaring than in Ohio, according to Brown. Between 2004, when George W. Bush won the state, and this year, the urban share of the electorate stayed the same, and the suburban vote increased by six percentage points. But the rural share declined by six percentage points. "The problem points to the rural voter just not showing up," she said.

Brown says the heated Ohio GOP primary race between Romney and Rick Santorum was evidence that the former Massachusetts governor had a difficult time connecting with voters who could have handed him the state in the general election. "It is fascinating to look at the total number of votes Santorum earned in 41 rural counties, which was 127,795" - and to note that Romney lost Ohio to Obama by about 107,000 votes.