It has been said by many on the right, including Milton Friedman, that the left's obsession with how money influences our politics is overblown. Here is an interesting paper that shows at the very least that the concerns of the rich have a higher probability of becoming law than the concerns of the poor.
Here is Kevin Drum:
I've written before about Larry Bartels' research showing that politicians basically don't care about the views of low and medium-income individuals. The non-rich simply have no impact on their voting behavior at all. But I know you want more evidence. So here it is.
The charts below come from a 2005 paper by Martin Gilens (a revised 2007 version is here). His study is based on a dataset of polling questions about public policy issues between 1981 and 2002 (raising the minimum wage, sending U.S. troops to Haiti, requiring employers to provide health insurance, allowing gays to serve in the military, etc.) in which the responses differed significantly between the rich and the poor. On the left, you can see the impact that support from low-income voters had: when 10% of them supported a position, there was about a 32% probability of that change becoming law. When 90% supported a position, there was a....33% probability. The chart on the right shows the same for median income voters. They did slightly better, but not much.
Rich voters, on the other hand, had a much better chance of getting their way, as the steep solid line in both charts shows. Why? Gilens' guess is that "the most obvious source of influence over policy that distinguishes high-income Americans is money." This sounds like a pretty good guess to me.
As The Economist covered this topic with the title: "government of the rich, by the rich, for the rich". They go on to say:
"Rich Democrats and rich Republicans elect politicians with a diverse range of views, but all of which ultimately respond to the policy preferences of the rich. To put this slightly differently, we all know rich people on the left side of the political spectrum who care passionately about the poor and have no problem supporting policies that aren't necessarily in their own direct interest. These people exist. But the Democrats who end up in Congress tend not to be these people; they're the kind of people who respond to the preferences of the rich. Who knows what their motivations for doing so are; perhaps they view concessions to rich priorities as necessary in order to survive in Washington to fight for other priorities some other day. And it should be noted that the priorities of middle and low income voters are occasionally heard and addressed.
But the asymmetry here shapes the policy that emerges from Washington. Legislators worried about the poor often have to cut deals to satisfy the rich people who support their campaigns and other critical institutions. Legislators worried about the rich basically never have to make these kinds of concessions. Money, by creating this asymmetry, gets what it wants much more often. As Mr Gilens notes, this is a feature of very nearly every political system in very nearly every historical era. What I would suggest is that it is therefore not a tremendous threat to democracy, except in cases when mobility levels across incomes fall dramatically. In that case, you create a permanent class of politically disenfranchised people. And that can be a very destabilising thing."