Part of proving or demonstrating “one of us” is to discuss legislative records: What have you done for me lately and how is it evidence that you are serving the best interests of
How can the average voter make any sense of these claims? As with all things, it depends on how you look at the records of both candidates. I am going to present three ways of thinking about Senator Tester’s and Congressman Rehberg’s records. I am going to present some additional data that will help you contextualize those records. Using this information, I provide some brief commentary but will largely leave it to Montanans to draw their own conclusions about the claims of both campaigns about their own records and the records of their opponents.
In general, the claims made by the campaigns about themselves and their opponent revolve around three distinct concepts:
Party Unity: How often does the member vote with their party in Congress?
Ideology: How liberal or conservative is the member?
Presidential Support: How often does the member support the president’s legislative agenda?
There are a number of ways these concepts can be empirically measured. Here are some standard measures utilized by political scientists that we’ll examine:
Party Unity: There are many ways to measure party unity, but the most common measure is produced annually by Congressional Quarterly since the late 1950s. CQ defines a party unity vote as a majority of one party opposing the majority of the other party on a given vote. To be specific, if 51% of Republicans vote yea on a motion and 51% of Democrats vote Nay, that vote meets the minimum standard to be included as a party unity vote. A party unity score is the percentage of times a member votes with their party on all party unity votes cast in a given year. The percentage of party unity votes as a percentage of all votes cast in Congress has ebbed and flowed throughout the years—the mid-1970s were a low point, while the last twenty years has seen a rebound in the number of votes clearly dividing the parties. Party unity scores have also increased over the late 20th and early 21st centuries, meaning members of the House and the Senate have become more loyal to their parties and less likely to break partisan ranks. Averages today are typically in the high 80s to low 90s in both chambers, with the House usually exhibiting more party loyalty than the Senate.
Ideology: One way to measure how liberal or conservative a member is to use DW-NOMINATE scores. DW-NOMINATE is a measure of ideology created by Poole and Rosenthal in their seminal work, Congress: A Political-Economic History of Roll Call Voting. Essentially, DW-NOMINATE takes the all the votes cast in Congress over time and develops factors which explain the variation found in those votes. The first dimension score Poole and Rosenthal call ideology, and this measure places members of Congress on a left-right dimension. Positive scores approaching 1 are more conservative, while negative scores approaching -1 are more liberal. It is important to note that both parties have become increasingly polarized after 1975, which means the average Democrat has become more liberal and the average Republican more conservative in both the Senate and the House. The other important thing to note is that both parties have become more ideologically homogenous—meaning moderates have become increasingly rare. More information on NOMINATE and NOMINATE scores can be found at Keith Poole’s website here.
Presidential Support: Again, Congressional Quarterly has set the standard for developing a measure of Presidential Support. CQ determines whether the presidential administration has taken a clear and public position on legislation. If the administration has, the vote on taken on that legislation is included in the universe of votes utilized to calculate an individual legislator’s presidential support. Simply put, a presidential support score is the percentage of times a member of the House or the Senate has voted to support legislation on which the administration has taken a public position. Higher scores indicate more support for the administration, lower scores less support. Traditionally, administrations receive the bulk of their support from their parties in Congress—with support of the administration’s positions from the opposition party declining in recent decades. Congressional Democrats often support Democratic administrations, and Congressional Republicans support Republican administrations.
Below, I have created a series of graphs depicting the voting records of the Montana congressional delegation between 2001 and 2011. In each instance, I plot the party unity, ideology, and presidential support scores for Senators Tester, Baucus, Burns, and Congressman Rehberg. I also provide contextual information, namely the average scores for Democrats and Republicans in both chambers. Finally, I wrap up the discussion with some concluding thoughts and by examining key congressional votes to see if that information tells a story that is any different from these more general measures of party unity, ideology, and presidential support.
The first chart plots the party unity scores of Montana’s Senate delegation and compares it to the party means in the chamber. Again, a party unity score is the percentage of time the member votes with their party when the majority of each party is in opposition. The second chart plots Congressman Rehberg’s party unity score relative to his party’s average scores.
Figure 1: Party Unity in Montana's Senate Delegation, 107th-111th Congresses
Figure 2: Congressman Rehberg's Party Unity, 107th-111th Congresses
How liberal or conservative is Montana’s Congressional Delegation? NOMINATE scores help sort this out. The first chart plots the first dimension DW-NOMINATE values of Montana’s Senate delegation, the second plots Congressman Rehberg relative to his peers in the House.Figure 3: Montana's Senate Delegation and Ideology, 107th-111th Congresses
Figure 4: Congressman Rehberg's Ideology, 107th-111th Congresses
How often did Presidents Bush and Obama receive support from Montana’s Congressional delegation? The final two charts show us. Again, the first chart is the CQ Presidential Support score plotted for Senators Burns, Baucus, and Tester and the second chart is Congressman Rehberg relative to his Republican peers.
Figure 5: Montana's Senate Delegation and Presidential Support, 107th-111th Congresses
Figure 6: Congressman Rehberg's Presidential Support, 107th-111th Congresses
In general, we learn the following from these measures of party unity, ideology, and presidential support:
1. Members of Congress generally support their parties on party unity votes.
2. Members of Congress generally support the administration when the administration shares their party affiliation.
3. Ideologically, Montana’s Democratic Senate delegation votes to the right of the average Senate Democrat. It is difficult to call either Senator Baucus or Tester a liberal—they are moderate or—perhaps more generously—conservative Democrats. Congressman Rehberg faithfully exists at about his party’s mean in the House—and quite possibly a tad to the left of the mean GOP member in the last Congress. Congressman Rehberg is conservative, but his conservatism is not extreme relative to his peers. He’s no Ron Paul or Randy Neugebauer, both representing Texas and two of the most conservative members of the Republican delegation in the House.
Three different ways to consider the legislative records of Montana’s congressional delegation. Overall, the picture is far more complex and nuanced than we might expect given the campaign rhetoric we hear on Montana’s airwaves, read in our inboxes, and a view on Facebook.