This study reinforces the notion that morningness and eveningness as explicit identities are associated with political ideology: Author found a relationship between morning orientation and conservatism

Political ideology and diurnal associations: A dual-process motivated social cognition account. Aleksander Ksiazkiewicz. Politics and the Life Sciences , First View , pp. 1 - 16, Apr 8 2021. https://doi.org/10.1017/pls.2021.4

Abstract: Social scientists have begun to uncover links between sleep and political attitudes and behaviors. This registered report considers how diurnal morning-night associations relate to political ideology using data from the Attitudes, Identities, and Individual Differences Study, a large-scale online data collection effort. Measures encompass perceived cultural attitudes and social pressures regarding diurnal preferences and explicit and implicit measures of both morning-night attitudes and morning-night self-concepts. Together, the analyses demonstrate a relationship between morning orientation and conservatism for explicit morning-night self-concepts and, to a lesser extent, explicit morning-night attitudes. This relationship is not present for implicit associations, and associations with perceived cultural attitudes and social pressure are also largely absent. This study reinforces the notion that morningness and eveningness as explicit identities are associated with political ideology.