The Philippines concluded its 2025 midterm elections on May 12—a high-stakes vote that tested the political capital of Bongbong Marcos, the country’s president and redrew the contours of power in one of America’s most pivotal Indo-Pacific allies. More than 18,000 posts were on the ballot, ranging from congressional seats to local councils, but the spotlight was firmly fixed on the 12 contested seats in the 24-member Senate. For Marcos, the results were sobering: a stinging rebuke in what was widely interpreted as a referendum on his leadership halfway through his six-year term.

Yet the implications of this vote reach far beyond Manila. As the U.S. leans on the Philippines as a bulwark against Chinese assertiveness in the region, the shifting political winds in the archipelago could complicate American strategic calculations. Central to the story is the rift between Marcos and his erstwhile ally, Vice President Sara Duterte, daughter of the country’s former strongman, Rodrigo Duterte. Once seen as an unbeatable populist duo, the two have since splintered into bitter rivals, their feud playing out in public—and at the ballot box.

Their alliance, forged during the 2022 elections, once united powerful dynastic machines. Marcos secured the presidency, while Sara Duterte claimed the vice presidency. But the cracks formed quickly. Accusations of corruption, threats of violence, and strategic purges followed. Duterte was ousted from the National Security Council and impeached by the House of Representatives; her fate now lies in the hands of the Senate.

Still, the Duterte brand has proven remarkably resilient. Sara remains a national political force and is widely seen as the frontrunner for the 2028 presidential race. Her father, despite facing charges at The Hague over extrajudicial killings linked to his infamous drug war, reclaimed the mayoralty of Davao City—his long-time stronghold. Rodrigo Duterte’s presidency was marked by frequent hostility toward Washington and an open flirtation with Beijing, including threats to scuttle the U.S.-Philippines Visiting Forces Agreement. His lingering presence ensures that the old playbook—nationalism tinged with anti-Western rhetoric—remains very much alive.

The midterms delivered a clear setback for Marcos. His allies managed to win only six of the 12 Senate seats—an underwhelming performance for a sitting president. Notably, only one of his supporters, broadcaster Erwin Tulfo, landed in the top six. Without a strengthened Senate majority, Marcos faces an uphill battle to advance his agenda and pursue Duterte’s removal from office. What’s more, a fragmented Senate may soon become a staging ground for rival presidential bids.

This domestic drama has strategic consequences. The results serve as a reminder that U.S.-Philippines relations cannot be taken for granted. Had Marcos prevailed decisively, he might have succeeded in sidelining the Dutertes. Instead, their grip endures, raising serious questions about the country’s long-term trajectory—and Washington’s influence over it.

Rodrigo Duterte famously ignored the 2016 tribunal ruling favoring the Philippines in its territorial dispute with China, choosing instead to vilify the U.S. while chasing grandiose infrastructure promises from Beijing—none of which fully materialized. Even after leaving office, he remains a vocal critic of Washington, accusing it of dragging the Philippines into conflict and casting doubt on American defense commitments.

Sara Duterte shares her father’s combative tone. She routinely lambasts the Marcos administration but avoids criticizing Beijing, even as Chinese incursions escalate in the South China Sea. Her silence has drawn criticism from members of her own government, underscoring her divergence from the current administration’s pro-U.S. stance.

By contrast, Marcos has pursued a starkly different course. He has embraced Washington, expanded the Enhanced Defense Cooperation Agreement (EDCA), and launched transparency campaigns to expose Beijing’s coercive behavior. His administration has also extended security dialogues to encompass Taiwan, further tightening the U.S.-Philippines strategic bond.

For now, this alignment is likely to hold. Philippine public opinion continues to identify China as the country’s primary security threat. However, the resurgence of the Duterte faction signals that this consensus may not be politically sustainable. The elections have made it clear: invoking the China threat is no longer sufficient to unify the electorate. The U.S. must prove—through deeds, not words—that it is a dependable partner.

To that end, Washington should prioritize tangible cooperation: pushing forward a trade deal, increasing military support, and staging joint exercises, such as the recently concluded Balikatan drills. These efforts should be embedded within a broader regional strategy, leveraging alliances with Japan, Australia, and multilateral groupings like the Quad to bolster Manila’s resilience. Initiatives like the Luzon Economic Corridor are promising avenues for embedding long-term strategic and economic ties.

The midterms revealed a country divided—not on whether China poses a threat, but on how best to respond. Marcos has three years left to demonstrate that his approach delivers results. The U.S., in turn, has three years to show that its partnership offers more than platitudes. If it fails, the door remains open for the return of a Duterte presidency—and with it, a potential unraveling of one of America’s most strategically vital alliances in the Indo-Pacific.