Unless you are brain dead, or work for the National Review1, you wouldn’t ever claim that Barack Obama is the most liberal Senator2.
How Liberal Interest Groups Rate the Senators (2007)
Many interest groups rate senators on how they vote. Well-known groups that issue such ratings include Americans for Democratic Action (a progressive group) and the American Conservative Union (a conservative group). In the table below, we give the ratings of seven such groups and the mean value for each senator. However, the ratings are not completely independent. Usually senators who get a good rating from the ADA get a bad rating from the ACU and vice versa. If we used four progressive groups and four conservative groups, every senator would probably get a score of 50%–not very interesting. To avoid this problem, we have only used (relatively) progressive groups. If you are a progressive, a senator with a high score is a good senator (supports everything progressive). If you are a conservative, a senator with a low score is a good senator (opposes everything progressive). In this way the differences between the senators stand out clearly. The table below is sorted on mean rating.
The .csv file is here, if you want to do your own sorting.
Per my quicky analysis, there is no way anyone can claim with a straight face that Obama is the most liberal Senator. Liberals such as myself have to come up with other reasons for supporting Obama – which, for the record, isn’t that hard to do – but liberal support isn’t because Obama is a Paul Wellstone acolyte. The numbers agree.
Some number crunching:
Per ACLU: Obama is 21st.
Per ADA: Obama is 46th.
Per CDF: Obama is 57th.
Per LCV: Obama is 50th.
Per NAACP: Obama is 3rd.
Per NARAL: Obama is 4th.
Per SEIU: Obama is 27th.