Despite the fact that they purport to represent us, they seem to be unaccountable to us. They must be elected to office, which means that a very large number of people must know their names and associate positive things with that name. To achieve this, they buy air time. The outstanding drawback to this practice is that it costs a lot of money. In order to purchase enough advertising to be elected, they solicit campaign contributions.
Individual citizens donate money, but so do businesses.
Some businesses donate a lot of money, like Phillip Morris and Chrysler. Businesses rarely part with money without some perception that doing so will help them to make more money. They expect to have influence with politicians they donate to, while the politicians wish to continue to receive campaign contributions. The lawmakers become beholden to corporations. Our interests became secondary to the interests of major contributors.