Wednesday, August 3, 2011

PVI Analysis of Mecklenburg County Precincts

Following the controversy of the North Carolina General Assembly stepping in and finalizing the district boundaries for the Mecklenburg County Board of Commissioners, I looked at the precincts and their voting behavior at the presidential level to see about developing a Partisan Voting Index analysis. Using the 2004 and 2008 presidential election results at the county-wide level, here are the results for the 195 precincts:


  • Likely Republican precincts (those precincts which, on average, voted 10% or above the county average for Republican presidential candidates in '04 & '08): 72


  • Lean Republican precincts (those precincts which, on average, voted anywhere from 3-10% above the county average for Republican presidential candidates in '04 & '08): 19


  • Toss-up precincts (those precincts which, on average, voted anywhere from +2 Republican to +2 Democrat, compared to the county average for presidential candidates in '04 & '08): 13


  • Lean Democratic precincts (those precincts which, on average, voted anywhere from 3-10% above the county average for Democratic presidential candidates in '04 & '08): 26


  • Likely Democratic precincts (those precincts which, on aveage, voted 10% or above the county average for Democratic presidential candidates in '04 & '08): 65
Here's a map depicting the precincts with their PVI classifications.



What is striking to me is how much Mecklenburg County is fitting into a model described by Bill Bishop in his book "The Big Sort" and in Dante Chinni and James Gimpel's work "Our Patchwork Nation." Bishop, in particular, notes that communities are "becoming even more Democratic or Republican. As Americans have moved over the past three decades, they have clustered in communities of sameness, among people with similar ways of life, beliefs, and, in the end, politics" (5).



In comparing the recent Mecklenburg County Commission districts, known as Stetson 5 and LM Plan B, we find that the districts break down as follows in both plans:


Stetson 5 plan (you can access the data here):



  • Proposed District 1: R+10.8%

  • Proposed District 2: D+23.5%

  • Proposed District 3: D+22.5%

  • Proposed District 4: D+10.0%

  • Proposed District 5: R+14.4%

  • Proposed District 6: R+14.6%


LM Plan B (you can access the data here):



  • Proposed District 1: R+11.4%

  • Proposed District 2: D+20.4%

  • Proposed District 3: D+21.9%

  • Proposed District 4: D+13.2%

  • Proposed District 5: R+11.5%

  • Proposed District 6: R+16.9%

Both of these plans basically draw districts designed to elect one party over the other, as was the charge of the current county commission to the redistricting committee.