Partisan communication in two-stage elections: the effect of primaries on intra-campaign positional shifts in congressional elections

The influence of congressional primary elections on candidate positioning remains disputed and poorly understood. We test whether candidates communicate artificially “extreme” positions during the nomination, as revealed by moderation following a primary defeat. We apply a scaling method based on candidates language on Twitter to estimate positions of 988 candidates in contested US House of Representatives primaries in 2020 over time, demonstrating validity against NOMINATE (r > 0.93) where possible. Losing Democratic candidates moderated significantly after their primary defeat, indicating strategic position-taking for perceived electoral benefit, where the nomination contest induced artificially “extreme” communication. We find no such effect among Republicans. These findings have implications for candidate strategy in two-stage elections and provide further evidence of elite partisan asymmetry.