MANILA— While Davao City Mayor Sara Duterte-Carpio remains the most popular prospect for next year's presidential elections, her lead in a Pulse Asia survey was "not too significant," the pollster said on Wednesday.

The Sept. 6 to 11 opinion poll of 2,400 people showed support for President Rodrigo Duterte's daughter, dropping from 28 percent to 20 percent as other potential candidates cut into her lead.

Sen. Manny Pacquiao, who announced his retirement from boxing on Wednesday to run for the presidency, rose one notch to fourth, with 12 percent support, up from 8 percent previously.

Ahead of Pacquiao with 15 percent was the son and namesake of late dictator Ferdinand Marcos, who has yet to confirm his plans, plus Manila Mayor Isko Moreno Domagoso, with 13 percent.

Duterte-Carpio's lead is "not too significant a margin; a percentage point," said Pulse Asia president Ronald Holmes.

"If you apply the margin of error, 1 out of 5 do prefer her. And her other contenders, contenders who are in double digits [are] not that far," Holmes told ABS-CBN News.

"And if you look at for example 'yung (the) level of approval of the administration, in the past you had the president getting significant majority. Despite that, only a fraction, 1/5 of the voters expressed support for Sara," he added.

Duterte-Carpio this month said she would not seek higher office, despite topping all surveys on prospective candidates ahead of registration, which opens on Friday.

Her ties to a political family could be a double-edged sword, Holmes said.

"Any elected official that has come from the known political family would definitely have an advantage when it comes to the name that would mobilize some support," he said.

"On the other hand, it may also repel some voters who don't necessarily agree or do not support that particular family... It can be disadvantageous for people... who don't think we should elect members of a political family who have other relatives in office."

Previous surveys showed the public "is essentially divided as regards whether it wants to support members of political families or vote for members of political families," said Holmes.

Duterte-Carpio’s brothers serve as vice mayor and Congress representative of Davao City.

Her father cannot run for a second term and will seek the vice presidency.

• ANALYSIS: Pulse Asia says Sotto survey lead over Duterte is 'significant'

The latest Pulse Asia survey showed Senate President Vicente Sotto III overtaking Duterte as the top contender to become vice president, which in the Philippines is a separate contest. Duterte dropped to 14 percent from 18 percent.

Sotto, a former actor and comedian, won 25 percent support, a big jump from his 10 percent in the previous poll.

Duterte's decision to seek the largely ceremonial position has been met with skepticism, with critics convinced he has ambitions to retain power, or remain in high office to stymie possible legal action over thousands of state killings in his notorious war on drugs.

Duterte said he wants to serve the public.

His aides earlier said he would not seek the vice presidency if Duterte-Carpio runs in the 2022 race.

"No one gets a clear advantage" when it comes to potential candidates backing out of the elections, said Holmes.

"We've seen this in previous elections when people speculate that most of the votes [for] Candidate A will go to Candidate B. The surveys will show no that's not the case," he said.

"More often than not, those who prefer candidate a who bows out of the race would tend to go to not just one but several other candidates."

— With reports from RG Cruz, ABS-CBN News; Reuters

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