Religion, Ideology, and Antipetismo in the 2018 Brazilian Presidential Elections

Abstract

Introduction: The 2018 Brazilian presidential elections disrupted the traditional PT–PSDB polarization and led to the rise of Jair Bolsonaro, a candidate supported by behavioral conservatism, religious nationalism, and antipetismo (hostility toward the Workers’ Party, PT). This study examines how religion, ideology, and partisan sentiments shaped electoral support for Bolsonaro in the first round of the 2018 elections through the mediating effects of conservative ideology and antipetismo. Materials and methods: We used data from the 2019 Latin American Public Opinion Project (LAPOP), which includes 1,498 nationally representative face-to-face interviews. A Generalized Structural Equation Model (GSEM) was applied to estimate direct, indirect, and total effects. Four recursive models were tested: three specifics to Catholics, Protestants, and Pentecostals, and one full model. Dependent variables included vote choice for Bolsonaro, antipetismo, and ideological self-placement on the right, controlling for sociodemographic and attitudinal variables. Results:Antipetismo and conservative ideology emerged as the strongest predictors of voting for Bolsonaro, increasing the likelihood of support by 224% and 101%, respectively. Approximately 60% of the ideological effect was mediated by antipetismo. The most pronounced pattern was observed among Pentecostals: identifying as Pentecostal increased the likelihood of voting for Bolsonaro by 122% and right-wing self-placement by 79%, with 21% of the effect mediated by ideology. Catholics showed a significant effect on antipetismo (44%) but no significant influence on ideology. Protestants exhibited only a direct effect on voting (76%), with no meaningful mediation. Discussion: The results confirm antipetismo as the main driver of the electoral cleavage in 2018, operating in conjunction with conservative ideology. A distinct “religious right,” with electoral impact mediated by ideological values, was observed only among Pentecostals. Among Catholics, antipetismo was linked to traditional socioeconomic factors, whereas Protestants exhibited a direct effect on voting without consistent ideological cleavage. This study contributes by decomposing heterogeneous causal mechanisms across religious denominations, highlighting the varied ways in which religion, ideology, and partisan sentiments shape electoral behavior.