Representatives have always belonged to some interest group. Their profession, their religion, whatever.
So9
That is a factor only insofar as they vote on things affecting the interest groups they belong to. Many times they vote on things that are not. In these cases their decisions will be affected by the people he meets expressing their opinions. In these situations access is the issue. Lobbying is a way of life in DC, and I think much of the unnecessary growth of the federal govenrment is because of the influence of special interest groups, not the least of which is the federal bureaucracy itself.