MANILA - Former Philippine National Police chief Ronald "Bato" Dela Rosa said Friday he was flattered by results of an opinion poll, which showed him as among the frontrunners in the 2019 senatorial elections.

However, Dela Rosa said he was still waiting for the go signal from President Rodrigo Duterte, as he was also eyeing the governorship of Davao del Sur.

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"I'm flattered but it is still too early to decide," said Dela Rosa, who retired on Thursday after being at the forefront of the government's war on drugs for nearly 2 years.

Dela Rosa will soon head the Bureau of Corrections, where he set a goal to end the drug trade in the national penitentiary.

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Apart from Dela Rosa Davao City Mayor Sara Duterte and broadcaster Erwin Tulfo were among the top contenders for the 2019 senatorial race, according to the survey.

The survey that was conducted from March 23 to 28, 2018 using face-to-face interviews, asked 1,200 adult respondents to choose from a list of 58 names. -- report from Bianca Dava, ABS-CBN News