The politics of SD’s representatives in Congress since 1971

In my story today on Stephanie Herseth Sandlin drawing fire from the left, I used a political science tool along with quotations to examine the question of Herseth Sandlin’s ideology. DW-NOMINATE was designed by political scientists Keith Poole and Howard Rosenthal to analyze voting patterns in Congress — going all the way back to the very first Congress.

It’s pretty complicated, and I barely understand it, so I’ll just say that one of the products of DW-NOMINATE is a score that reflects how liberal or conservative a lawmaker’s voting record is on economic issues. (For quite some time, this has correlated very highly with voting patterns on non-economic issues, political scientist Jeff Lewis, who has also worked with DW-NOMINATE, said.)

Here are the DW-NOMINATE scores for South Dakota’s members of Congress dating back 40 years. The figures are all ratings for the entire career in Congress. The scale runs from -1 (most liberal) to +1 (most conservative): 

Over the time covered by the dataset, but for all states and not just South Dakota, the most liberal Democrat had a score of -.784 — very close to Jim Abourezk, who actually ranks as the fourth most liberal member of Congress during this entire period. (He’s behind short-time Sen. Carte Goodwin, D-W.V., ex-Rep. Craig Washington, D-Texas, and Rep. Barbara Lee, D-Calif.) The median Democrat nationwide had a score of -.356 — just a bit to the left of Tom Daschle, and considerably to the left of both Tim Johnson and Herseth Sandlin.

The most conservative Republican nationwide had a score of .989, far more conservative than any of South Dakota’s Republicans. (That’s current Sen. Mike Lee of Utah, though his sample size of votes is very small. In a close second place is Sen. Jeff Flake of Arizona. In fourth place is ex-Rep. Ron Paul of Texas.) The median Republican nationwide had a score of .362, just to the left of John Thune and Kristi Noem, and considerably to the right of Larry Pressler, Jim Abdnor, the short term of Bill Janklow and Karl Mundt.