This is a great video that explains a little history of corporations and the Supreme Court case Citizens United v. FEC. More money was spent by independent groups during the 2010 elections than all of the other midterm elections since 1990 combined, with the U.S. Chamber of Commerce spending the most. This, at a time when 85% of Americans believe corporations have too much power in our democracy. We need to stop supporting politicians who primarily support the desires of corporations over individuals, and hopefully the precedent from the Citizens United case will be overturned sooner than later.
Here's an equally great, but much shorter, video on the same topic from Ben and Jerry of Ben and Jerry's Homemade, Inc.