Modeling electoral dynamics for the Portland, Oregon city council

This study aims to understand the representational outcomes likely under the new STV system in Portland, OR, with particular attention to the potential for electing POC-preferred candidates. We also seeks to give recommendations for political organizers including strategic decisions about how many candidates to run and how best to tailor mobilization efforts to maximize their effectiveness.

We explore the complexities of the new STV system by simulating voter behavior across sce- narios that vary the number and type of candidates as well as varying voters’ cohesion along ideolog- ical and demographic lines. We divide voters either coarsely into two blocs (People of Color (POC) and White (W) voters) or more granularly into three (POC, White Progressives (WP), and White Moderates (WM)). Our models can be adjusted for candidate breakdown, perceived candidate strength, and voter group cohesion, with seven key cohesion scenarios split out to predict electoral outcomes in interpretable terms.

Our results suggest that both the number of POC candidates in play and the willingness of WP voters to support candidates primarily identified with communities of color are likely to be the strongest determinants of outcomes in the November election.