Members of Congress are getting richer while the average American isn't. Peter Whoriskey of the Washington Post reports that between 1984 and 2009, while the median wealth of American households edged down from $20,600 to $20,500, the median wealth of a member of the House of Representatives grew from $280,000 to $725,000 (in inflation-adjusted dollars and excluding home equity in both cases). That means the average member of Congress went from being 13.6 times as wealthy as the average American to being 35 times as wealthy.
It's not that members of Congress are earning so much more money than they were in the past—in fact, House pay has declined since 1977—but that the people running for and being elected are a lot richer than they used to be. More rich people, fewer blue-collar workers. It's tough to nail down exactly how and to what extent that affects the day to day workings of Congress:
But a person’s financial circumstances certainly affect a person’s political outlook. For example, people identified as lower or middle class have been more likely to see income inequality as a problem and to favor redistribution of income, according to figures from the General Social Survey. [...]
A representative’s occupation before being elected influences how liberal or conservative he or she is in voting, according to an analysis of more than 50 years of congressional votes by Duke University professor Nick Carnes.
In order from most conservative to most liberal: farm owners; businesspeople such as bankers or insurance executives; private-sector professionals such as doctors, engineers and architects; lawyers; service-based professionals such as teachers and social workers; politicians; and blue-collar workers, according to the analysis, which is being published in Legislative Studies Quarterly.
Surprise! When you have a government made up of rich people and people whose financial lives are defined by what they own, it turns out that you have a government that reflects the interests and beliefs of the ownership class. There are, of course, exceptions, rich people who nonetheless care passionately about the wellbeing of working people or blue-collar workers who believe they will shortly own their own plumbing businesses and therefore need to care most about rich people, but on average, not so much.