Standard theories of electoral competition predict that politicians should converge toward the centre as elections approach. This column challenges this prediction, using 3.4 million tweets from 367 political leaders across 21 Western democracies. Rhetorical polarisation between populist and non-populist leaders rises sharply in the two quarters before an election and reverts to average levels once it is over. Both groups adopt a more emotionally direct communication style as elections near, but they increasingly talk about different topics. The findings suggest that social media turns electoral campaigns into an engine of political polarisation.

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10 April 2026

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Vox EU

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https://cepr.org/voxeu/columns/when-and-why-political-leaders-polarise-rhetoric-evidence-twitterx

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