A few days after last November’s election, I posted some predictions about the partisan makeup of the new Congress. In the process, I discussed which representatives and Senators would be pivotal players over the next two years. These predictions were based on DW-NOMINATE scores, which describe the partisanship of members of Congress based on their voting records. These scores range roughly from -1 to 1, and generally, the more positive a member’s voting score, the more conservative his or her voting record is. The newest batch of DW-NOMINATE scores, including votes from 2010, was released a couple weeks ago, so I’ve updated the info I posted last November.
I have made one major change since I wrote this post (I suggest that you go read it if you want some background on DW-NOMINATE scores and why I’m focusing on particular members of Congress). I am now using the DW-NOMINATE “Common Space” scores, meaning both representatives and Senators are mapped along the same line, making their scores comparable and allowing us to more accurately predict the scores for Senators with previous experience as a representative. Also, I should note that this score incorporates every vote a member of Congress takes throughout his or her career.
First, let’s look at the House. The graph below shows the distribution of representatives by DW-NOMINATE scores in the 111th (2008-10) and 112th (2010-12) Congresses. For those new representatives with no experience in Congress and therefore no score, I assumed they were distributed like the other members of their party in the House (among representatives, there were 8 Democrats and 85 Republicans which had no score).
As I noted last year, the left side of the Democratic party remains intact, while the right flank has shrunken considerably. On the right, since I assumed that all new representatives were distributed like those who I already had scores for, the result is pretty much the same distribution, just larger.
After incorporating last year’s votes, the voters around the median in the 111th Congress (2008-2010), and their scores, were as follows:
- 213. Steve Driehaus (D-OH), -0.234
- 214. Jerry McNerney (D-CA), -0.233
- 215. Gary Peters (D-MI), -0.233
- 216. Betsy Markey (D-CO), -0.232
- 217. Lincoln Davis (D-TN), -0.230
- 218. John Boccieri (D-OH), -0.228
- 219. Bill Owens (D-NY), -0.227
- 220. Bart Gordon (D-TN), -0.227
- 221. Stephanie Herseth Sandlin (D-SD), -0.222
- 222. Michael McMahon (D-NY), -0.220
- 223. Suzanne Kosmas (D-FL), -0.219
The projected voters around the median for the next two years are the following:
- 213. Shelley Moore Capito (R-WV), 0.245
- 214. Todd Platts (R-PA), 0.247
- 215. Rodney Frelinghuysen (R-NJ), 0.260
- 216. Peter King (R-NY), 0.263
- 217. Leonard Lance (R-NJ), 0.266
- 218. Mike Turner (R-OH), 0.268
- 219. Jo Ann Emerson (R-MO), 0.273
- 220. Don Young (R-AK), 0.274
- 221. Frank Wolf (R-VA), 0.280
- 222. Jeff Fortenberry (R-NE), 0.292
- 223. Candice Miller (R-MI), 0.305
I have not included any new representatives because I do not have their scores, though their approximate positions were considered in determining who would be near the median.
In the Senate, using the “Common Space” metric is useful because now we can have more confidence in the approximations for new Senators who used to be Congressmen. The distribution of Senators in the 111th and 112th Congresses are shown below. When a new Senator did not have a score (which was the case for one Democrat and six Republicans), I made a ballpark guess as to where they might end up.
The Democrats have lost some Senators from all parts of the spectrum, and most of the new Republican Senators are either mainstream or more conservative Republicans (Senators in the middle and to the right of the Republican distribution).
There are 53 Democrats in the Senate, but they need 60 to break a filibuster. Where will those other votes come from? The ten Republican Senators with the lowest DW-NOMINATE scores (roughly, the least conservative) are shown below. The Democrats would probably need to get at least 6 or 7 of these votes in order to pass legislation through the Senate:
- 54. Olympia Snowe (R-ME), 0.085
- 55. Susan Collins (R-ME), 0.108
- 56. Scott Brown (R-MA), 0.180
- 57. Mark Kirk (R-IL), 0.224
- 58. Lisa Murkowski (R-AK), 0.237
- 59. Thad Cochran (R-MS), 0.292
- 60. Richard Lugar (R-IN), 0.326
- 61. Chuck Grassley (R-IA), 0.329
- 62. Lamar Alexander (R-TN), 0.331
- 63. Kay Bailey Hutchison (R-TX), 0.358
The one name that stands out to me on this list is Mark Kirk, of Illinois. Now that I am using the common space metric, he has been placed further to the left, between Scott Brown and Lisa Murkowski, on the partisan spectrum. It also seems like the most difficult leap will be between 58 and 59, where the “yes” votes have to extend from Senators Brown, Kirk, and Murkowski to Senators Cochran, Lugar, or Grassley.