Barack Obama campaigned four years ago assailing George W. Bush for wage losses suffered by the middle class - more than three years into Obama’s own presidency, those declines have only deepened

The rebound from the worst recession since the 1930s has generated relatively few of the moderately skilled jobs that once supported the middle class, tightening the financial squeeze on many Americans, even those who are employed. As a candidate in 2008, Obama blamed the reversals largely on the policies of Bush and other Republicans. He cited census figures showing that median income for working-age households -- those headed by someone younger than 65 -- had dropped more than $2,000 after inflation during the first seven years of Bush’s time in office. Yet real median household income in March was down $4,300 since Obama took office in January 2009 and down $2,900 since the June 2009 start of the economic recovery, according to an analysis of census data by Sentier Research, an economic- consulting firm in Annapolis, Maryland. Ninety-five percent of the net job losses during the recession were in middle-skill occupations, such as office workers, bank tellers and machine operators, according to research by economists Nir Jaimovich of Duke University in Durham, North Carolina, and Henry Siu of the University of British Columbia in Vancouver. The job growth since has been clustered in either high-skill fields inaccessible to workers without advanced education or low-paying industries, they found. In March 2012, 3.2 million fewer Americans held sales and office jobs than five years earlier, and 1.2 million fewer were employed in transportation and production fields, all areas that typically pay middle-income wages, according to the Bureau of Labor Statistics.