Articles and Analysis


Out of Step or Out of Office? (Or Just a Bad Election for Republicans?)

Topics: 2006 , The 2006 Race

Today's Guest Pollster Corner Contribution comes from Simon Jackman of Stanford University, who takes a closer look at Tuesday's Senate election results. 

Two interesting questions to ask after Tuesday's election are (1) Were the six defeated Republican senators particularly "out of step" with their respective states?; (2) What will be the effect of the Democratic pickups on the look of the new, 100th Senate?

To answer this question I first assigned a liberal-to-conservative voting score to each senator based on an analysis of the 530 non-unanimous roll call votes cast in the 109th Senate. The resulting scores are scaled to have mean zero and standard deviation 1, with lower (negative) scores reflecting a more liberal voting history, and positive scores reflecting a more conservative voting history (the details of this scoring procedure appear in my 2004 article with Josh Clinton and Doug Rivers in the American Political Science Review. A familiar story results, with Democrats on the left, Republicans on the right, with virtually zero no overlap between the parties. Lincoln Chafee is estimated to be the most liberal Republican with a voting score of about zero, while Ben Nelson (NE) is the most conservative Democrat (again, with a voting score close to zero). The usual suspects anchor the extremes of both parties: Barbara Boxer (CA) and Ted Kennedy (MA) for the Democrats (scores of -1.9), and Inhofe (OK) and Demint (SC) for the Republicans (scores of 1.3).

To gauge each state's political complexion, I use a simple and convenient proxy: Bush's share of the 2004 presidential vote in each state, which ranges from a high of 71.5% in Utah, to a low of 36.8% in Massachusetts, with a median of 52.7% (bracketed by Florida's 52.1% and Missouri's 53.3%).

The graph below shows a scatter-plot of voting score against 2004 Bush vote. Each point corresponds to a senator (red for Republicans, blue for Democrats, with senators running for re-election given a heavier shading), with 2004 Bush vote on the horizontal axis, and the roll call voting score on the vertical axis (higher is more conservative, lower is more liberal). The gray line is a regression fit to the data, not to be taken too seriously, but rather more as a rough guide as to how "out of step" the senator may or may not be. Republicans running for re-election are all numbered: Republican senators losing their seats are numbered 1 through 6, the other Republican senators who were re-elected are numbered 7 through 14. Chafee (RI), Santorum (PA) and Allen (VA) seem to be the only Republican losers who are obvious candidates for a "out of step" with their state kind of story (along the lines proposed by Canes-Wrone, Brady and Cogan in a 2002 article in the American Political Science Review, lying relatively distant from the regression line. DeWine (OH) seems to have been caught in what was an extremely difficult election for Republicans in Ohio, and neither Talent (MO) nor Burns (MT) appear to have been particularly "out of step". And keep in mind that there are several Republican senators just as apparently "out of step" as Santorum or Chafee who did not lose their seats: e.g., Jon Kyl (AZ), who faced no Democratic opposition in 2000, but won 53-44 in 2006; or John Ensign (NV), who by almost identical margins in both 2000 and 2006.


It is interesting to speculate on shape of the new, 110th Senate. Chafee goes, replaced by a Democrat, leaving the Maine senators (Olympia Snowe, re-elected with a 74-21 margin in 2006, and Susan Collins) as the most moderate Republicans. It remains to be seen just how liberal or moderate the new Democrats will be. Given their states and the narrow margins with which they are projected to win, it is tough to imagine Webb (D-VA) or Tester (D-MT) being particularly liberal, perhaps voting more like relatively conservative Democrats from the plain states (e.g., Nelson, NE; Conrad and Dorgan from ND) or the other Montana senator (Baucus).



Its also interesting that if you drew a regression line for Republicans only, and a seperate line for Democrats only, you could get two parallel lines separated by a vertical distance of about 1.0. This would suggest that when a state replaces a Republican with a Democrat, on the average the replacement will be 1.0 units more liberal, and when a Democrat is replaced by a Republican, the replacement will be 1.0 units more conservative.


Gary Kilbride:

By the time Webb is up in 2012, Virginia could be a 50/50 or slightly left leaning state.

Montana has been voting close to 60% red in presidential races but the state has no trouble preferring Democrats in statewide races. I think secretary of state is the only statewide office Republicans hold in Montana. There may not be a major challenger to Tester in 2012. Plus he's a likable guy and a great fit for the state. This could easily be a case of a huge initial hurdle then relatively easy re-elects for several cycles.

Sherrod Brown is the intriguing case, IMO. Despite the curious torture vote he's significantly more liberal than the state prefers. If revealed a year ago, Brown's margin would have stunned me more than any senate result. The state fury toward Republicans is likely temporary plus most of the GOP house members survived the wave, and one or more may be positioned to try for senate in 2012.

To outsiders, John Ensign's results will never make sense in terms of the Nevada presidential margins.The state has only three variables: Clark, the Cows, and Washoe. The rural cow counties favor the GOP by 2/1 or more. Washoe (Reno) is the swing region, slight edge toward the Republican (Kerry lost by 4) but a strong Democrat can win the county. Clark (Las Vegas) has 70+% of the votes in the state, with a Democrat needing at least +7 to +10 in Clark County to prevail statewide.

Ensign thwarts that blueprint since he has unusual strength in Clark County, specifically NV-1 which he held from '94 to '98. Then Ensign ran in '98 and '00 for senator, losing by 400 votes to Reid in a statewide hand recount in '98 before winning an open senate seat in '00. The voters in Las Vegas know him well, that's what I'm saying. Every cycle from '94 thru '00 Ensign was on the ballot in Clark County. Previously he was a well known veterinanian in Las Vegas. Unless he's remarkably masochistic and votes pro-Yucca Mountain or anti-gambling, Ensign will always pull a number out of Clark County that makes it virtually impossible to deny him statewide.



There is some interesting work on singular-value-decomposition analysis of the roll call votes, such as this one by Porter et al.


Kibitzer 2006:

Very interesting. There is one other point that you might want to consider. There are many factors that influence how a state's senatorial vote may go. A simple liberal/conservative measure (such as Bush's 2004 performance) misses a lot of things. You might consider throwing in an indicator variable for the incumbent's party, as a crude surrogate for those other factors.

I tried to do a visual fit to just the Republican incumbents. I'm sure my visual fit is not perfect, but it looked to me as though the 6 Rs that lost were about evenly spread on both sides of the R-only regression line. More interesting, of the 8 Rs who won their races, 2 were above the line and 6 were below.

I tried to do the same thing with the Democrats/Independent and found that all but 3 of the 16 incumbent winners were above that line. It's a little hard to draw too many conclusions since we didn't see any D/Is lose, but maybe part of that is that they were generally more centrist.

Maybe what you have found is a shift toward the center, all other things being equal?

Is the data available anywhere?




What no one has commented on (that I've seen) is that Webb in Virginia won the military districts. He got the majority of votes in Norfolk and Newport News. This affects some of the assumptions above -- the military vote has been traditionally Republican, but the Iraq war and dislike of Rumsfeld by military staff may have changed that. In fact, it seems as though most of the former military running for Congress were Democrats in this election. Military may have a conservative tinge, but it's not the current kind of conservative (religious, anti-abortion, etc.) but the old Republican fiscal conservative. I think the definition of conservative may be the real issue here...


Brendan (KS):

Plain states? Them's fightin' words.

However, if you meant Plains states, we'll readily agree to that characterization.


tom veil:

Tamar -- I noticed that too after reading a Washington Post map. Webb also won Quantico by a small margin and Arlington by a landslide.


Post a comment

Please be patient while your comment posts - sometimes it takes a minute or two. To check your comment, please wait 60 seconds and click your browser's refresh button. Note that comments with three or more hyperlinks will be held for approval.