Sen. Hillary Rodham Clinton declares, “The economy is not working for middle-class and working families,” noting the typical American family earns less now than it did seven years ago. Citing the same trend, her Democratic presidential rival, Sen. Barack Obama, promises “to put America back on the path to prosperity.” Sen. John McCain, the likely Republican nominee, says, “It is harder for families to weather hard economic times.” The candidates’ pitches are aimed at wooing the vast majority of Americans who consider themselves middle class. Those people tell pollsters that they are increasingly anxious about their financial security, a feeling that has intensified in recent years because of flattening wages, rising income inequality, increasing consumer debt, soaring health-care costs, spiraling energy prices and, now, declining home values. But as Americans’ wage growth has slowed, their rate of consumption has accelerated, leaving some economists dubious about claims that the middle class is worse off than before.