Why has the distance between the parites increased over time?

Exogenous - things that are going on outside of congress

1. Member Replacement
   
   1. CIVIL RIGHTS
      
      1. Dems became civil rights party. Very polarizing
      2. African Americans now allowed to vote
      3. Replacement of Conservative Southern Dems
   2. Conservative democrats are being replaced by even more conservative republicans. And now places where conservative democrats were holding office are now being held by liberal democrats. (east coast + NE)
   3. Why took so long? Usually takes a member to retire to replace old conservative southern democrats, replaced by more conservative republicans
2. Redistricting
   
   1. i. Drawn to pack districts with one ideology, move to the extreme
3. Primaries + role of activists

II. Endogenous - within congress

1. Change in cultural norms in the house and senate-
   
   1. members spend much less time in Washington than they used to. There is much more cooperation along party lines because they are never in town.
   2. The seniority system has dropped off in importance
      1. Committee chairs used to serve forever
         1. Starting in the 70s, a major vote in caucus can remove chairs
         2. Term limited the time one could serve as committee chair (6 years)
2. Changes in Rules
   1. Party leadership has packed rules committee with the most loyal members
      1. Rules committee sets the docket and can place rules on bills (ie no amendments), as well as amend themselves
         1. Manage what is in the bill and only give members limited options to vote against it
      2. Who makes the decision on who goes to the conference committee? The leadership now.
         1. Created to resolve disagreements on a particular bil
3. Leadership More Ideological -
   
   1. leaders are better at raising money because PACs give money due to ideology.
   2. Role of activitsts increased in primaries
   3. Congress tends to be more polarized already, leaders follow
   4. Theoretically, more ideological leaders just draws the compromises further to your side of the political spectrum