New research reveals that partisan gerrymandering can paradoxically increase competition in congressional elections during favorable national conditions, due to adverse short-term effects on the map-drawing party. This "dummymander" effect is common and has significant implications for understanding election outcomes.

The study analyzes 40 years of congressional elections. Contrary to expectations, partisan gerrymanders often lead to greater competitiveness in seats held by that party when national electoral tides favor them.

Key findings:

● Partisan redistricting increases district-level competition during favorable national election cycles

● Bipartisan and nonpartisan maps show consistently lower rates of induced competition

● The effects are most pronounced under short-term national forces driving up competitiveness expectations

These results suggest that partisan mapmaking, often criticized for suppressing competition, can sometimes have the opposite effect. This has important implications for scholars studying political polarization, representation, and electoral dynamics.