From a current article in Boston Review, Martin Gilens reports the conclusions of his research into the links between public policy and public preferences:
In most circumstances, affluent Americans exert substantial influence over the policies adopted by the federal government, and less well off Americans exert virtually none. Even when Democrats control Congress and the White House, the less well off are no more influential.
The 99ers community can definitely attest to the lack of influence we've had since the start of the Great Recession. The floor is littered with the pages of bills that were introduced, only to die in committee.