One-Sided Advertising Affects Vote Choice: Opposition to Maine’s Pine Tree Power

• In Event: Climate Change Technology, Public Opinion, and Misinformation

Abstract

Although voters tend not to be well-informed about the policy issues on the ballot in referendum elections, they can often rely on cues from trusted political leaders to make choices in line with their preferences. However, some policy issues divide party leaders, sending mixed signals to voters. How do voters make up their minds in these circumstances? The case of Pine Tree Power, an initiative on the Maine ballot in November 2023, offers insight into this question. The initiative would have replaced private electric utilities Central Maine Power (CMP) and Versant with a consumer-owned, nonprofit utility governed by an elected board. Elected officials within both major parties failed to reach consensus on the initiative, precluding voters from relying on the party heuristic to determine their vote choice.

In this context, astroturf organizations funded by CMP and Versant spent nearly $40 million to defeat the initiative, primarily through television and digital advertisements. These ads made multiple disputed claims–that the proposal would cost Mainers $13.5 billion, that it could increase taxes, and that Pine Tree Power did not have a plan for how to operate Maine’s electric grid. Although prior results on the effects of advertisements on voting in ballot initiative elections are mixed, research is needed on cases of one-sided spending, where voters receive a steady diet of arguments for one side of the campaign. In Fall 2023, we conducted a survey of 755 Maine voters and 14 semi-structured interviews to examine how voters made their decisions on Pine Tree Power in the presence of one-sided spending.

Our interviews and qualitative survey data suggest that voters largely used a memory-based model to form their preferences, relying on immediately accessible considerations. Given the absence of clear partisan cues and the ubiquity of advertisements, we posit that voters relied on the advertisements to guide their decisions. To test this hypothesis, we estimate the effect on vote choice of being exposed to advertisements about Pine Tree Power “often” or “very often.” We find that voters who were regularly exposed to such advertisements were about 10 percentage points less likely to vote for Pine Tree Power. This estimate is robust to the inclusion of county fixed effects and to sensitivity analysis. We argue that the utility-backed advertising campaign influenced voters’ decisions, contributing to Pine Tree Power’s defeat at the ballot box.

Authors

• Geoffrey Lancaster Henderson, University of Michigan

• Nicholas F. Jacobs, Colby College