Assessing congressional districting in Maine and New Hampshire

TL;DR

This paper analyzes the political geography of Maine and New Hampshire using voting data, revealing significant deviations in district boundaries likely caused by incumbent gerrymandering, and discusses limitations of fairness measures for two-district plans.

Contribution

It introduces a data-driven analysis of districting in Maine and New Hampshire, highlighting gerrymandering effects and limitations of classical fairness metrics.

Findings

District boundaries differ significantly from expected patterns.

Gerrymandering likely influences districting decisions.

Classical fairness measures have limitations for two-district plans.

Abstract

We use voting precinct and election data to analyze the political geography of New Hampshire and Maine. We find that the location of dividing line between Congressional districts in both states are significantly different than what we would expect, which we argue is likely due to incumbent gerrymandering. We also discuss the limitations of classical fairness measures for plans with only two districts.