It’s also interesting that Republicans aren’t grouped based on geographic distribution, while Democrats are still broken out as “Southern Democrats” and “Northern Democrats”. As you can tell from the graphs, the Democratic party has become increasingly dominated by “Northern Democrats” (the line for Democrats in general becomes insignificantly different from the line for Northern Democrats by the 1980s, whereas the line for Democrats in General USED to be about half way between Northern and Southern Democrats from the 1930s until the late-’60s).As an interesting “precursor” to the above charts, it’s good to remember that party politics prior to 1880 were rather tumultuous. Remember the Tory party? The Federalists? The Whigs? The Anti-Federalists? (http://umlud.blogspot.com/2012/07/the-permanent-two-party-system-is.html )What the above charts shows me is that the Republican Party is either going to return from its march toward conservatism or it’s going to fracture. If the former, it seems likely that the Democratic Party will come to include more “blue dogs” (thus marching them slightly more conservative). If the latter, then it seems likely that the Democratic Party will lose membership of current conservatives (who will move to join in the new, not-as-conservative-as-the-Republicans Party), but will also become slightly less conservative.Of course, the whole system could continue to limp along, since it’s maintained and propped up by the expected reality of there being a two party system made up of these two parties, who would prefer to survive as THE ONLY two parties. (The system of elections, gerrymandering, institutional inertia, and a whole boatload of social relationships only help to dissuade and minimize the possibility at any loosening of the hold that the Democrats and Republicans have on near-exclusive political power.)