SARA Duterte leads Leni Robredo in OCTA Research’s latest solo presidential test. Put Robredo together with Raffy Tulfo, however, and the picture changes.
In OCTA’s Q2 2026 head-to-head presidential survey, Duterte received 43 percent against Robredo’s 34 percent. In a hypothetical tandem test from the same Q2 fieldwork, Robredo-Tulfo registered 45 percent against 42 percent for Duterte-Imee Marcos. With a national margin of error of plus or minus three points, that is a statistical toss-up. It does not mean one survey is right and the other is wrong. It means the questions are asking voters to imagine two different political contests — one where voters choose a single name, another where they evaluate a package. And in the Philippines, where the president and vice president are elected separately, that distinction matters. That’s the paradox. The map changes In OCTA’s March survey, Robredo-Tulfo led Duterte-Marcos nationally, 44 to 40, with 16 percent undecided. The regional divide was already stark: Robredo-Tulfo led 61-23 in NCR, 57-23 in Balance Luzon and 48-40 in the Visayas. Mindanao was the mirror image, with Duterte-Marcos ahead 86-5. By Q2, the structure remained polarized, but the movement was telling. Robredo-Tulfo stood at 56-22 in Luzon and 61-23 in Balance Luzon. The Visayas had moved to a 45-45 tie. Mindanao became even more lopsided: Duterte-Marcos, 90; Robredo-Tulfo, 5. The national result therefore hides two opposing political maps. Robredo-Tulfo’s competitiveness comes from enormous Luzon margins and enough strength in the Visayas to offset Duterte-Marcos in Mindanao. Duterte-Marcos, meanwhile, starts with a southern base so overwhelming that it can absorb substantial losses elsewhere and remain competitive nationally. This isn’t just about who leads which region — it’s about how big those margins are, and whether they’re big enough to survive erosion elsewhere. The Visayas question The most consequential movement may be in the Visayas. In March, Robredo-Tulfo led 48-40. By Q2, that eight-point advantage had disappeared into a 45-45 tie. That matters because the Visayas sits between two political fortresses. Robredo-Tulfo can afford to lose Mindanao badly if it runs up sufficiently large margins in Luzon and remains competitive in the Visayas. Duterte-Marcos can survive large Luzon deficits if Mindanao remains overwhelming and the Visayas moves in its direction. If I had to pick one region to watch, it would be the Visayas, not Mindanao. Duterte-Marcos does not need to win Luzon if its Mindanao advantage remains overwhelming. But between March and July, Robredo-Tulfo’s eight-point Visayas lead disappeared into a tie. If that movement continues, the national arithmetic could shift quickly. If Robredo-Tulfo takes the region back, Duterte’s extraordinary Mindanao margin becomes less decisive. What does the tandem add? The harder question is why the tandem format changes the race at all. Pollsters can’t tell us whether Tulfo hands Robredo a bloc of voters, or simply gives undecideds a reason to pick a side — and no tandem survey can answer that. What the results do suggest is that political combinations can reach voters differently from individual candidates. Robredo alone trails Duterte in the solo test. Robredo-Tulfo, as a tandem, becomes nationally competitive. That does not prove Tulfo delivers a fixed bloc to Robredo. It suggests the pairing may broaden the coalition available to the ticket. The same question applies on the other side. Duterte-Marcos remains extraordinarily strong in Mindanao but continues to lag badly in Luzon. If the pairing is supposed to expand beyond Duterte’s base, the numbers so far suggest that work remains unfinished. Class tells another story The March cross-tabs also suggest that the coalition divide is not purely geographic. Robredo-Tulfo led among Class D respondents, 47-39, while Duterte-Marcos led Class E, 51-36. Among ABC respondents, the two tandems were essentially even at 35-37. Those subgroup figures should be read cautiously because their margins of error are wider than the national estimate, but they reinforce the same point: the national total is being assembled from very different constituencies. For either tandem, expanding the coalition means more than protecting a regional base. It means finding voters outside the social and geographic groups already most comfortable with the ticket. The limits of the exercise A tandem survey has obvious limits. Filipinos do not vote for president and vice president as a single ticket. They can split their choices. Some voters who prefer Robredo for president may not choose Tulfo for vice president, and the reverse is also true. The election also remains far away. Alliances can change. Candidates may not run. Political and economic conditions will move. These surveys are snapshots of how voters react to hypothetical configurations today. But repeated snapshots can still reveal something useful: The race is not simply about the popularity of individual candidates. It is also about coalition architecture. The presidency is elected one office at a time. But these numbers suggest voters aren’t necessarily imagining 2028 that way yet. If that persists, the pairing may matter almost as much as the candidate. Bong Habana Ruado is a former public-sector official whose career has spanned government, politics, public policy and the private sector. His current interests include public opinion research, governance data and explanatory journalism, with a particular focus on interpreting political surveys beyond their headline numbers. He holds degrees in political science and law (Juris Doctor) and completed the Strategic Business Economics Program at the University of Asia and the Pacific.
