MANILA, Philippines — Vice President Sara Duterte's lead over former vice president and current Naga City Mayor Leni Robredo in a hypothetical 2028 presidential matchup has narrowed to seven percentage points, the smallest recorded by OCTA Research in its 2026 surveys, as the number of undecided voters continued to increase.
Duterte obtained 40 percent against Robredo's 33 percent in the third-quarter Tugon ng Masa survey conducted from September 28 to October 4 among 1,200 adult Filipinos nationwide.
The seven-point margin was down from 11 points in the first quarter, when Duterte registered 46 percent against Robredo's 35 percent, and nine points in the second quarter, when the figures stood at 43 percent and 34 percent, respectively.
OCTA said Duterte's preference had declined by six percentage points over the three survey rounds, while Robredo's remained relatively stable, ranging from 33 percent to 35 percent.
The proportion of respondents who chose neither candidate or did not know whom to vote for rose to 26 percent in the latest survey, from 22 percent in the second quarter and 19 percent in the first quarter.
The growing undecided bloc suggests that voters moving away from Duterte have not necessarily shifted their preference to Robredo, OCTA said.
Despite the narrowing margin, Duterte remained ahead nationally, with her seven-point lead outside the survey's plus-or-minus three-percentage-point margin of error.
The survey results also showed significant regional differences in the hypothetical matchup.
Robredo led Duterte in the National Capital Region, with 39 percent against 32 percent, and in Balance Luzon, where she received 49 percent against Duterte's 24 percent.
Duterte, meanwhile, maintained a commanding lead in Mindanao, with 71 percent against Robredo's 2 percent. She also led in Visayas, 46 percent to 27 percent.
