Formalization of the Opposition Alliance in Turkey: the Cases of the 2018 and 2023 General Elections

In recent years, opposition leaders in competitive authoritarian regimes have increasingly engaged in various forms of electoral coordination to improve their chances of unseating incumbents. Such opposition coordination has taken different forms. In some cases, opposition parties relied on informal or quasi-formal arrangements, including issue-based cooperation that stopped short of routinized and formalized alliances. In others, they pursued more formalized strategies, such as nominating joint candidates, running joint campaigns on a shared platform, and developing transparent post-election power-sharing arrangements. While existing scholarship highlights the electoral advantages of opposition coordination, there is limited research on why opposition parties opt for different degrees of formalization in their pre-electoral alliances and how they address coordination and commitment problems under regime uncertainty. This paper examines the conditions under which opposition coordination is formalized. Using a most similar systems design, we compare opposition alliances in Turkey’s 2018 and 2023 general elections. Whereas the main opposition Republican People’s Party (CHP) formed a quasi-formal alliance with three right-wing parties that failed to select a joint presidential candidate and a common parliamentary list in the 2018 general elections, the same party leadership succeeded in constructing a more formalized and comprehensive pre-electoral alliance in the 2023 general elections. The paired comparison shows that formalization of a pre-electoral alliance is incentivized by two factors: (1) increased regime vulnerability and (2) pronounced power asymmetries among opposition parties. These findings contribute to literature on opposition behavior under electoral authoritarianism and offer broader implications for understanding opposition alliance formation in constrained political settings characterized by high uncertainty.