Party divisions within the Socialist Party over the 2027 nominee selection process remain the central driver of trader sentiment, with internal factions split between a broad left-wing primary and a party-specific moderate candidate. Recent confirmation of a primary has kept multiple contenders viable, including Boris Vallaud and Raphaël Glucksmann as leading options alongside Olivier Faure, while figures like François Hollande and Ségolène Royal stay in reserve. This fragmentation, combined with stalled negotiations among left parties and competition from La France Insoumise, sustains a wide field and closely matched probabilities. Scheduled party congresses and primary timelines through late 2026 could consolidate support or trigger shifts if alliances form or prominent candidates clarify their intentions.