The Chairmen

Among Minnesota's Democratic congressional delegation there are two in top leadership positions; Jim Oberstar is Chairman of the House Transportation and Infrastructure Committee and Colin Peterson is Chairman of the House Agriculture Committee. Both have represented the state for a long time; Oberstar for over 25 years, Peterson for close to 20, and both represent large, mostly rural districts. But as we saw with their respective SILVER scores, they are quite different in how they vote, at least in the 111^th congress. While Colin Peterson had a slightly liberal for his district score of -.06, Jim Oberstar had a superstar level -.55. Let's take a look at their DW-Nominate scores over the entire course of their time in office to see if that changes our perception any.

What you see is that over the years Oberstar has become marginally more conservative while Peterson has made moves in the liberal direction. This becomes even more evident when you look at their current scores for the 111^th congress versus their mean and first year scores.

	111	mean	1st	+/- mean	+/- 1st	stddv
PETERSON	-0.175	-0.139	-0.103	-0.036	-0.072	0.0242
OBERSTAR	-0.539	-0.544	-0.550	0.005	0.011	0.0033

As we saw earlier, in the 111^th congress Peterson is voting more liberally then he has in the past and Oberstar is voting slightly more conservatively. What you can also see by looking at the standard deviation of their scores, as well as the +/- versus the mean and first year, is that Peterson's voting patterns have shifted more substantially over the years then Oberstar's, who has essentially the same score now as when he started.

What does this mean? Well, Jim Oberstar has been voting the same way for 25 years and Colin Peterson has ever so slightly become more liberal than when he first joined the congress. If we assume the PVI of the 7^th CD is the same now as it was in 1991 (a dubious assumption) then Peterson would've had a SILVER score of .08 in his first congress, compared to the -.06 he has so far this congress, a -.14 swing in the liberal direction. It's probably not incidental that his vote share has also risen steadily over the years to 72% in 2008. While Colin Peterson is no liberal, he is liberal for his district and getting more liberal every year.