What influences might cause a member of congress to vote agnist the wishes of the people from his/her district or county?

3 answers

Us.government ^^

Consider this news from our newspaper this evening. Republican Congressman Fred Upton is known as a "nice guy," even to the Democrats of his district. He has generally voted for what he considers best for his moderate and largely rural district. Yet this article explains how he's being torn between two different political realities.

http://www.mlive.com/news/kalamazoo/index.ssf/2010/11/republicans_debate_whether_con.html

Anything else more general?