Reinforcement in the Aggregate: Partisan Newspaper Circulation and the Presidential Vote, 1900-1928

While generally understood as an individual-level effect, we argue that reinforcement effects-or the strengthening of existing party loyalties through media exposure-might also play a role in shaping aggregate-level outcomes. Looking across eight presidential elections from 1900 to 1928, this study provides evidence that partisan newspaper circulation was significantly linked to two-party vote share at the county level. Counties with higher circulation rates of Republican dailies had a smaller percentage of votes cast for the Democratic presidential candidate, while a weaker positive association was found between the circulation of Democratic leaning dailies and Democratic vote in non-Southern counties. Some variance in this effect was observed across elections, with some evidence suggesting a weaker association between circulation and vote share as newspapers moved away from overtly partisan content toward a more professional tone. Further, some of the relationships were reciprocal with votes influencing partisan circulation. Results suggest that greater attention be given to the role of the political media environment and how citizens engage with it when understanding macro-level political outcomes.