You can change who's in office, but it's basically impossible at this point to change the offices themselves. Committees and subcommittees, lobbies, corporations, military interests and other support systems are so entrenched that it literally doesn't matter who you put in power, the same problems will exist.

Anyway, Congress isn't supposed to get along. If everyone agreed all the time we would be able to reduce the system to a single person who made all the decisions. The point to a representative democracy is that the representatives represent different interests. Even the idea of having a vote presupposes conflict.