Problem
In a decentralized, individualistic institution such as Congress, it is not obvious how its members will behave. However, it has become increasingly true that members of Congress are deeply polarized along deep partisan divisions and that is why the voting patterns of the members of each party in Congress has tended to align in more than 90% with the party's caucus.
There are three theories or views that aim to explain how members of Congress, once elected, behave:
Representational explanation: Since members want to be reelected, they will vote according to their constituents' preferences and therefore to please their constituents (Constituents over Party position).
Organizational explanation: Since most constituents do not know how their legislator has voted, it is not essential for the legislators to their constituencies. They will respond and behave responding to cues provided by colleagues from their same party (Party over Constituents position).
The attitudinal explanation: There are so many conflicting pressures on members of Congress that they cancel one another out, leaving every member of Congress to vote on the basis of their own beliefs. This means that if they are elected on a strong partisan view and due to a strong activists' participation, then they will be more ideological in their way to vote and in their willingness or unwillingness to compromise with other members of Congress (Each member behaving according to his/her beliefs = Ideology First Position).
Each intergroup discussion should decide which theory or combination of theories best explains how members of Congress, once elected may behave and why.