Montana Congressional Delegation Ideology Redux

In reference to my previous post, a reader asked me where former Senate Majority Leader Mike Mansfield fit ideologically in Montana's congressional delegation. Well, since I am a data nerd, I went and collected and graphed the Common Space scores for the entire Montana delegation from the 80th through the 112th Congresses. I didn't go back further than that because there's an argument to do so would distort the data. Poole and Rosenthal caution about making comparisons in ideological scores across party eras, and if we still believe in realignment theory as a useful frame to think about American politics (and there is great debate about this, see David Mayhew's book The End of Realignment), then it makes sense to restrict this analysis to the post-World War II era. In any case, the previous point still holds: Rehberg is not quite as conservative as folks might have us believe (he is in the middle of the Republican pack). Jon Tester and Max Baucus are moderate, ideological centrists--especially when compared to their co-partisans historically. You can grab these data yourself at Keith Poole's website here.

One last note. The numbers are slightly different from the previous version because new common space scores have been calculated using new information from the 112th Congress. In the aggregate, the patterns remain the same. If anything, the new numbers show Rehberg slightly more to the left and Tester closer to the right and Baucus. Interestingly, Baucus hasn't moved a whit (perhaps because of his long tenure and the massive numbers of votes he's taken--additional information shouldn't add much explanatory power to his ideological position).

And thanks to the reader who asked the question. This was a fun diversion!

P.S. Right click on the image to enlarge it.