The academic literature on project sponsorship is quite rich. In the past Top Management Support is a topic that seems to be picked up once a decade (Young and Jordan, 2008). More recently TMS or project sponsorship has attracted more attention with Bucero (2024) being one of the most recent contributions.
The following Connected Papers link and schematic is provided to help readers explore the literature further: Project Sponsor Effectiveness and Project Success | Connected Papers
Bucero, A., 2024. Project Sponsor Effectiveness and Project Success. European Project Management Journal, 14(2), pp.3-16.
Young, R. and Jordan, E., 2008. Top management support: Mantra or necessity?. International journal of project management, 26(7), pp.713-725.