The survey, conducted on March 21-28, showed support for Sen. Aquino, son of the country's democracy icon Cory Aquino, has been steady at 37 and 36 percent so far in 2010, although below a peak of 45 percent in December.
Support for billionaire Manuel "Manny" Villar dropped 4 points to 25 percent in March, and is now 10 points below his January reading, the poll of 3,000 people found.
Former President Joseph Estrada, ousted from office in 2001, and administration candidate Gilberto Teodoro remained third and fourth respectively, with their support steady at 18 percent and 7 percent.
Teodoro's inability to raise his single-digit support has raised expectations supporters of President Gloria Macapagal Arroyo might switch camps, and some key power brokers have already swung behind Villar.
That may have hurt Villar. The Aquino camp has labelled him 'Villarroyo', tagging him as candidate of a president who is widely unpopular due to several corruption scandals during her nine years in office.
Media reports have said Arroyo's husband was supporting the presidential bid of Villar, who in turn has tried to publicly distance himself from the president and her family.
Aquino, who is hoping the wide support and popularity of his late mother would translate to votes, has vowed to fight corruption and restore good governance. He has said he would start probes into allegations of corruption against Arroyo.
The results of the opinion poll, which have a 2 percent margin of error, results were posted on the Pulse Asia website http://www.pulseasia.com.ph/ The results in the Pulse Asia poll are similar to those in an SWS poll released last week.
