Leading Philippine presidential candidate Benigno Aquino has seen his margin narrow sharply to single digits in the race against property titan Manuel Villar for May's election, a poll showed Friday.

Senator Aquino, 51, had risen to the top of the polls from nowhere on a popular outpouring of sympathy following the death last year of his mother, democracy icon and former president Corazon Aquino.

With less than four months to go before the May 10 ballot, Manila-based Social Weather Stations said its December 27-28 national survey of 1,200 adults had Aquino polling 52 percent to fellow senator Villar's 44 percent in a theoretical two-horse race.

A similar survey it conducted on October 1-4 had Aquino ahead by a massive 37 percentage points at 65 percent to Villar's 28 percent.

The surveys had an error margin of three percentage points.

Eight candidates are contesting to succeed President Gloria Arroyo, who is disqualified by the constitution from seeking a second six-year term.

Social Weather Stations did not give a reason for the tightening of the race.

Villar, a 60 year-old property developer who is listed by Forbes magazine as the Philippines' ninth richest man with a net worth of 530 million dollars, has attacked the younger Aquino as an inexperienced neophyte.

Villar has meanwhile rejected rivals' allegations that he used his government position to enrich himself.

The six other candidates include deposed former president Joseph Estrada and former defence secretary and Arroyo's preferred successor Gilberto Teodoro. (AFP)