Former president Duterte wins mayoral race from Hague prison

Millions of Filipinos braved long lines and soaring temperatures on Monday to vote in a mid-term election largely defined by the explosive feud between President Ferdinand Marcos and impeached Vice President Sara Duterte.

With 75 per cent of precincts reporting, Senate candidates aligned with Duterte were on track to claim five of 12 seats up for grabs, an initial tally from the Commission on Elections (Comelec) released by local media showed.

The tally, if it holds, would give the vice president one more seat than predicted in nationwide polls — a potentially crucial vote in a looming Senate impeachment trial tentatively scheduled for July.

Former president Rodrigo Duterte, detained at the International Criminal Court (ICC) for alleged crimes against humanity, regained the mayorship of family stronghold Davao city in a landslide vote on Monday, an initial tally showed.

Former first lady Imelda Marcos prepares to cast her vote at a polling station in Batac City. AP

With over 77 per cent of returns in, Duterte had built an insurmountable lead of 635,948 votes to about 78,000 for his nearest competitor, results from the Comelec released by local media showed.

Two of Duterte's sons and two grandsons were also on track to capture public office in the city.

Five Senate hopefuls endorsed by Marcos and two independents appeared headed for election as the clock approached midnight. Monday's election will also decide more than 18,000 positions nationally, from seats in the House of Representatives to hotly contested municipal offices.

Detainees held at the Manila City Jail are seen during voting in the mid-term election. AFP

With temperatures reaching 34˚C in some places during the day, Comelec chief George Garcia said some voting machines had experienced "overheating."

"It's slowing the voting process," he told reporters at a prison in southern Manila where inmates were casting ballots. "Due to the extreme heat, the ink (on the ballots) does not dry immediately, and the ballot ends up stuck on the scanners," Garcia said, adding officials in some areas were resorting to aiming electric fans at the machines.

The heat had even turned the blue ink used to dye voters' fingers orange in the bottle, he said.

A Filipino checks his voter receipt after voting during the midterm elections, at a polling station in Taguig City, Metro Manila, on Monday. Reuters

Roland Agasa, one of the country's 68 million registered voters, said the feud between the Duterte and Marcos dynasties had taken a mental toll ahead of the election.

"The government is getting stressful," the 53-year-old said outside a Manila elementary school where a polling station was on the fourth and fifth floors. "I hope we choose the deserving, those who can help the country," Agasa said, adding he planned to wait until the day cooled before braving the stairs to vote.

Monday's Senate battle holds major implications for the presidential election in 2028. The 12 senators elected nationally will form half the jury in Duterte's impeachment trial, with a guilty verdict permanently barring her from public office.

The vice president needs nine votes in the 24-seat Senate to preserve any hope of a future presidential run.

Sara Duterte speaks to the media during a press conference after casting her vote at a polling center in Davao City. AP

Two candidates tracking to win, including the president's independent-minded sister Imee Marcos, were "adopted" as honorary members of the Duterte family's PDP-Laban party on Saturday.

The move to add Marcos and television personality Camille Villar to the party's slate was intended to add "more allies to protect the Vice President against impeachment", according to a party resolution.

Duterte's long-running feud with former ally Marcos erupted in February when she was impeached by the House for alleged "high crimes", including corruption and an assassination plot against the president.

As polls opened on Monday, two men were killed and seven wounded in the central Philippines when men fired on a group outside a local party headquarters from a moving vehicle.

The Philippines has a long history of election violence, with armed groups of political rivals routinely fighting over positions that control local government spending.

A day before, at least two people were killed in a clash between supporters of rival political camps in southern Mindanao island's autonomous Muslim region, the Philippine army reported.

National police have been on alert for more than a week, and around 163,000 officers have been deployed to secure polling stations, escort election officials and guard checkpoints.

Comelec last week said it had recorded 81 acts of "politically related" violence between January 12 and May 7. Police told AFP that 16 of those had resulted in death.

Agence France-Presse