Like most members of Congress who hope to keep their seats, Senator Treumann wants to do what his best for his constituency. Sometimes, however, he thinks that what is best is not necessarily what surveys show that most voters in his state want. He sees his vote against allowing more spending on surveillance for antiterrorism efforts in this light, thinking it best for the country and his state, no matter how popular. In this case, he would be serving as the classic ___________type of legislator.