Sara Duterte-Carpio, his estranged vice-president and fiercest political rival, has already declared her intention to run and remains the early front runner, despite an impeachment trial that could bar her from politics.Marcos said on August 14 that he would “certainly endorse a candidate” in 2028 but added: “Who that is I cannot tell you because even I don’t know.”The one candidate he almost certainly will not support is Duterte-Carpio, daughter of former president Rodrigo Duterte. Their 2022 alliance helped unite two of the Philippines’ most powerful political dynasties before collapsing into open war.By launching her 2028 presidential bid earlier this year, the vice-president set up a succession battle that could decide not only who controls the Malacanang presidential palace after Marcos’ single, constitutionally limited six-year term, but also whether the country swings back towards Duterte-style strongman politics and a more China-friendly foreign policy.A protester holds an image of former Philippine president Rodrigo Duterte with a message reading “Hold Duterte Accountable!”, during a rally in Quezon City in March. Photo: EPAOn paper, Marcos’ former allies have rarely looked more vulnerable.