Official results from the Philippines Election Commission shows key allies of detained former President Rodrigo Duterte and two liberal opposition candidates are among top winners in the nation's midterm Senate race.

Election officials say former Philippine President Rodrigo Duterte has been elected as mayor in his home city by a landslide, despite his detention by the International Criminal Court.

Despite the ICC's case also including alleged killings of criminal suspects by a "death squad" in Davao while Duterte was mayor - which he has denied - analysts have said his arre