The (in)stability and determinants of voters’ issue salience from a longitudinal and comparative perspective

Research agrees that individual-level issue salience, i.e. the importance that voters ascribe to different issues, is a fundamental determinant of political behavior. However, the commonly used measure of issue salience, i.e. the ‘most important problem’ question, complicates any research on individual-level salience beyond the most important issue. Consequently, there is a surprising lack of research on the determinants and over-time stability of individual-level issue salience. To fill this gap, we (a) theorize and investigate the over-time stability and determinants of individual-level issue salience, and (b) compare the determinants of voters’ issue salience and attitudes. Specifically, we focus on ten issues, evenly split between socioeconomic and GAL/TAN issues. We measure individual-level issue salience by asking respondents to assign low, medium, or high priority on a predetermined set of issues. We combine cross-sectional data from six Western European countries with longitudinal data from Germany (1984-2021), enabling a comparison across space and time. By looking at relevant predictors such as left-right ideology, education, age, assessment of the economy, and gender, we find considerable variation between the determinants of voters’ salience of socioeconomic and GAL/TAN issues. While education and age emerge as the prevailing factors in determining salience on socioeconomic issues, GAL/TAN issue salience is most consistently predicted by age and left-right self-placement. Surprisingly, gender does not determine the salience that voters ascribe to neither socioeconomic nor GAL/TAN issues. Further, our analyses reveal occasions in which some voters ascribe low salience to an issue while holding distinct attitudes towards the issue, potentially explaining why voters do not act in accordance with their attitudes: the issues they support/oppose are not always important to them. These results highlight opportunities for parties seeking to strategically select which issues to (de-)emphasize, at a time when both the highly salient socioeconomic issues and contentious GAL/TAN issues matter in structuring Western European political conflict. Overall, we contribute to the literature on individual-level issue salience by, first, theorizing and testing the stability and determinants of issue salience, and second, demonstrating the value of measuring issue salience across a wide range of issues, with broader implications for the understanding of political contestation and electoral competition in Western Europe.