Significant percentage of both WEALTHY & POOR view themselves as "MIDDLE-CLASS"
"...From Real Housewives to pop stars, extreme wealth is on display all around us. Seeing this, Americans imbibe ideas of what life as a rich person means. And most folks, even in the 1 percent (that is, with incomes above about $500,000), cant keep up with the Kardashians. They conclude they are not wealthy, so they tag themselves middle class. Were far less keen to have the poor in view. Nevertheless, whether via images of bread lines or real life panhandlers, we have some sense of life without means. If homelessness is the salient exemplar, people are unlikely to say theyre poor.
...Not finding popular depictions of wealth and poverty similar to our own lived experiences, we determine we must be whatevers left over. Picking middle class is easy enough to do because, again, the language doesnt present much to go on in terms of what this label describes.
The remaining economic component for all of our class designations isnt income but stuff you can buy. One common synonym for rich and poor is the haves and have-nots. But consumer goods once deemed luxuries, like cellular telephones and televisions, are now common possessions. This means that even as employers held tight to the gains our productivity generated by keeping real wages at 1970s levels, we sent women into the workforce, labored longer hours, and used new debt products to indenture our way to some happiness. Thus, our stand-in to signify class status purchasing power papers over the fact that by income, benefits, and lifestyle standards many of us had long left behind a middle-class existence, even as we clung to the moniker."
http://www.theatlantic.com/politics/archive/2013/08/why-americans-all-believe-they-are-middle-class/278240/
This, to me, goes a long way in helping to explain why so many people who barely have two quarters to rub together happily continue to vote Republican, and why an articulate message of economic populism resonates across party lines.