We investigate the antecedents of affective polarization in the American public, and focus specifically on the driving role of exposure to darker forms of campaign communication (negativity, incivility, populist rhetoric) and the intervening role of individual populist attitudes. Experimental evidence was gathered among a sample of US respondents (MTurk, N = 1,081); respondents were randomly exposed to a campaign message from a fictive candidate framed either positively or negatively, and afterwards asked to express their attitudes towards Democrats and Republicans. Results show that exposure to harsher forms of campaign negativity (character attacks associated with political incivility and populist messages) drives affective polarization upwards when compared to exposure to positive messages. We also show both a direct and moderating effect of populist attitudes: populist individuals are more likely to “like” negative campaign messages (they find them more amusing and fairer) and report higher levels of affective polarization. Furthermore, exposure to negative messages is associated with greater affective polarization particularly among respondents high in populist attitudes.

中文翻译：

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两极分化的民粹主义者：黑暗运动、情感两极分化以及民粹主义态度的调节作用

我们调查了美国公众情感两极分化的前因，并特别关注接触黑暗形式的竞选传播（消极、不文明、民粹主义言论）的驱动作用以及个人民粹主义态度的干预作用。实验证据是在美国受访者样本中收集的（MTurk，N = 1,081）；受访者被随机接触到来自虚构候选人的正面或负面的竞选信息，然后被要求表达他们对民主党和共和党的态度。结果表明，与接触积极信息相比，接触更严厉的竞选负面信息（与政治不文明和民粹主义信息相关的人格攻击）会导致情感两极分化加剧。我们还展示了民粹主义态度的直接和调节作用：民粹主义个人更有可能“喜欢”负面的竞选信息（他们发现这些信息更有趣、更公平），并报告了更高水平的情感两极分化。此外，接触负面信息与更大的情感两极分化有关，尤其是在民粹主义态度高的受访者中。