Republicans, Democrats and 'the Middle Class'

In both Tampa and Charlotte, speaker after speaker tried to identify with "the Middle Class" and echoed the theme of upward mobility and fulfillment of "the American Dream." That's been a staple of presidential campaigns since the end of World War II. But in recent decades, "the Middle Class" has been shrinking. Do Democrats and Republicans even agree any more on what "Middle Class" really means? Do potential voters still share "the American Dream?" We hear about traditional slogans, contemporary realities and this year's promises from both political parties.