The conventional wisdom is that Colombian President Juan Manuel Santos lost the most when voters rejected his agreement with the FARC guerrillas to end his country’s five-decade-old armed conflict, but the biggest losers may be the FARC itself, and its Cuban and Venezuelan allies.

Granted, Santos suffered an unexpected defeat. All major polls had predicted that his agreement with the FARC would be approved by a 2-to-1 margin. And the agreement’s signing ceremony in Cartagena — with several Latin American presidents in attendance along with United Nations Secretary General Ban Ki-moon — had given the peace deal a mantle of international support that seemed sure to help Santos win the referendum.

But the defeat of the 297-page peace accord has left the FARC commanders more isolated than ever, and facing an uncertain future.

Under the agreement, FARC leaders accused of war crimes would have received largely symbolic sentences — doing community work in restricted areas rather than going to jail — and would have been automatically granted five seats in the Senate and five seats in the House for the next eight years.

In addition, their estimated 7,000 troops would have received a significant income for several years to help reinsert them into civilian life. Many Colombians felt that the Santos government had given away too much in exchange for a deal that they thought would be difficult to enforce.

What will happen next? Among the possibilities:

l The best-case scenario: A successful renegotiation of the Santos-FARC peace agreement that leads to a new peace deal that would be accepted by most Colombians. Santos and the leader of the opposition to the peace accords, former president Alvaro Uribe, met Wednesday to discuss a new offer to the rebels.

But the Havana-based FARC leaders say they will never agree to jail sentences, or make other major concessions beyond the ones they have already made.

l The indefinite cease-fire scenario: The Santos government and the FARC rebels may maintain the cease-fire indefinitely while they pursue new peace negotiations. But military experts warn that as the rebels go back to drug trafficking and kidnappings to fund their troops, it will be hard to prevent clashes that could lead both sides to step up armed confrontations.

l The return to full-fledged war scenario: The FARC commanders could reject a new government peace offer and go back into hiding in Colombia. But while the FARC can continue to fund itself with illegal activities, it is running out of international backing and foreign safe havens.

It’s unclear how much longer the Venezuelan and Ecuadorean regimes will be able to cling to power. And Cuba’s octogenarian dictator is moving closer to Washington in hopes of resurrecting the island’s economy.

l The FARC slow-motion disintegration scenario: An article by U.S. Army War College professor Evan Ellis and Colombian security expert Roman D. Ortiz on the war college’s website suggests that many FARC rebels will leave the group.

“Although the internal cohesion of the FARC has always been limited, particularly with respect to the 1st and 7th fronts, whose autonomy has been bolstered by significant income from narco-trafficking, the rejection of the accords will make it even less manageable as a single organization,” they say.

While the FARC leadership will remain committed to peace negotiations, “the new uncertainty will decrease the number of middle rank commanders willing to take the risk of participating in the demobilization process, preferring a continued existence outside the law, living off illicit activities,” they add.

My opinion: The FARC commanders are now facing the possibility of a Uribe-backed, right-of-center candidate winning Colombia’s 2018 elections, which could result in demands that Cuba, Venezuela and Ecuador deny FARC members safe haven or extradite them. And there’s another possibility: By then, the FARC’s traditional allies in those three countries may be history.

None of this will mean the end of violence in Colombia. But we can’t rule out that one of the outcomes of Colombia’s referendum could be — as Ellis and Ortiz suggest — a slow-motion disintegration of the FARC, with its members joining smaller criminal bands. Whether that would be good or bad is something that deserves further study.

— Andres Oppenheimer is a Latin America correspondent for the Miami Herald.