That's sort of true.Just a note here. Senators aren't supposed to vote for what's best for the country, they are supposed to vote for what's best for their state.
Look, politicians have constituents. They run on certain ideas and platforms. Some people will support them just because they think its the right thing. Others will support them because they perceive it will be in their interest. Michigan pols consistently supported measures to help the auto industry. Minnesota pols consistently support measures to support dairy farming. They will support candidates who support their views. That'[s fine. That's democracy in action.
The alternatives are far too bad to imagine.