Explaining the Democrats’ Leftward Drift

The Geography of Politics, Part 2

In this post, I continue doing the job Minnesota’s political scientists can’t be bothered to do themselves.  In the first part of this series, I introduce this hypothesis: the safer a seat is for a given political party, the more extreme its holder will become, over time.

When a candidate can win a district without appealing to independents or to moderates of the other party, he or she has no incentive to moderate their views on the issues.  On the contrary, a moderate politician holding a safe seat is vulnerable to a challenge from the more extreme wing of his or her party.

Appeal to Evidence

Blogger Tony Petrangelo of the website LeftMN has calculated a partisan index for all 134 seats in the Minnesota House of Representatives.   

To oversimplify, an index of “even” (as is the case for my Edina district) indicates that the district’s voters do not display a tendency to vote for either Republicans or Democrats.  An index of R+1 or higher indicates that the district leans to the right.  An index of D+1 or higher indicates that the district leans to the left.

The higher the index number, the less likely it is that the district will be represented by someone from the opposite party.  According to Petrangelo, at present, no Republicans represent areas rated D+1 or above in the state House.  Several Democrats represent R-rated districts, including one district rated as high as R+6.

The conservative Taxpayers League of Minnesota has calculated a lifetime rating for all 134 members of the Minnesota State Legislature, based on each Representative’s voting record.  The League’s rating ranges from 0 to 100.  A rating of 100 would rank a legislator as one of the most conservative, a rating of zero would place a legislator among the most liberal.

In the chart below, I show each Republican House member’s League lifetime rating graphed against the partisan index of each member’s district, as depicted by the red dots.

The horizontal axis shows the partisan index. At present, no Republican holds a district seat rated as Democrat-leaning.  A score of “zero” on this axis means the district is rated as “even” between Democrats and Republicans.  Republican seats are rated up to R+17.

The vertical axis shows the League’s lifetime rating.

 

The dark dashed line shows the trend as we move up the vertical axis.  Consistent with my hypothesis, for Republicans, the safer the seat (the higher the partisan index) the more conservative the holder.

The one outlier shown in the graph is Jim Abeler, the Anoka Republican who represents a district rated R+6 and is rated by the League with a moderate lifetime score of 53 on the 0 to 100 scale.

As shown on the chart below, the situation with Democrats is similar.  However, the corresponding pattern for Minnesota’s Democrats resembles more an “L” lying on its side than the linear pattern of Republicans. 

In Search of:  Moderate Democrats

As before, the horizontal axis represents the district’s partisan index.  Democrats represent a number of Republican-leaning districts.  These districts are represented by positive numbers.  Districts with a D rating are represented as a negative number and range up to D+40 (graphed as -40) for the seat held by Minneapolis Democrat Karen Clark.

Supporting my hypothesis, the only Democrat-held districts with “moderate Democrat” representatives (League rating above 20) are rated as either Republican, Even, or no more than D+5.  These swing districts could elect a candidate from either party, so it’s understandable that Democrats who hold such seats would be more moderate than holders of safer D seats.

Applying the Hypothesis
If you buy the hypothesis, than a number of logical conclusions suggest themselves:

·       To get more moderate politics, you need more competitive seats.  This conclusion is certainly not original, with opposition to gerrymandering dating back centuries.  With so many seats in safe hands and so few competitive plays, the resulting gridlock and sharp partisanship should surprise no one.

·       Democrats have safer seats than Republicans.  This is not a conclusion, but an observation of the data itself.  A D+40 seat is safer than an R+17.  Democrats hold 19 seats rated safer than the safest Republican seats.

·       Democrats are further from the political mainstream than Republicans.  Applying my hypothesis leads to this conclusion.  A party lead by holders of seats rated +20 or above will be more radical than a party whose safest seat is only +17.  Democrats may have made inroads into Republican territory to gain a majority, but once in majority, Democrat leaders (Committee Chairs, Leadership) are from safe Democrat seats.