A senatorial election was held on November 9, 1965 in the Philippines. The Nacionalista Party wrestled back control of the Senate; originally a Liberal, Senate President Ferdinand Marcos defected to the Nacionalistas, became their presidential candidate and won this year's election. After the election, the Senate emerged with 12 Liberals on one side, and 11 Nacionalistas and 1 Nationalist Citizens' Party caucusing with them on the other.

Electoral system

Philippine Senate elections are held via plurality block voting with staggered elections, with the country as an at-large district. The Senate has 24 seats, of which 8 seats are up every 2 years. The eight seats up were last contested in 1959; each voter has eight votes and can vote up to eight names, of which the eight candidates with the most votes winning the election.

Retiring incumbents

Nacionalista Party

Mid-term vacancies

Other incumbents running elsewhere

These ran in the middle of their Senate terms. For those losing in their respective elections, they can still return to the Senate to serve out their term, while the winners will vacate their Senate seats, then it would have been contested in a special election concurrently with the next general election.

Results

The Nacionalista Party won five seats, the Liberal Party won two seats, and the Nationalist Citizens' Party (NCP) won one. NCP's Lorenzo Tañada, and Nacionalistas Alejandro Almendras and Genaro Magsaysay all defended their seats. Five winners are neophyte senators. These are Dominador Aytona, Eva Estrada Kalaw, and Wenceslao Lagumbay of the Nacionalistas, and Liberals Sergio Osmeña Jr. and Jovito Salonga. Estanislao Fernandez of the Liberal Party lost his seat.

Per candidate

Per party

Defeated incumbents