Updated

The stunning defeat on Sunday via referendum of a peace deal with left-wing guerrillas that would have ended Latin America’s longest-running civil conflict has left many observers and supporters of the accord wondering what happens now.

After years of negotiations between the Colombian government and the Revolutionary Armed Forces of Colombia (FARC) rebels, it seemed all but assured that – with polling inciting the referendum would win by an almost two-to-one margin – the deal would pass a popular vote.

But the 297-page accord included provisions that many found infuriating, such as sparing rebels jail time if they confessed their crimes and instead reserved them 10 seats in Congress.

A strong push by opponents of the deal and low voter turnout, however, saw the “No” vote win by a razor-thin margin, 49.8 percent to 50.2 percent.

Both Colombian President Juan Manuel Santos and FARC leadership have vowed to push ahead and maintain a cease-fire in a drug-infused war that left 220,000 people dead and displaced 8 million. But experts say that the options for Santos and the FARC are unclear and it could be a while before a viable path forward is found.

“The dust needs to settle before any real decisions are made on how to proceed forward,” Chris Sabatini, a professor at Columbia University’s School of International and Public Affairs (SIPA) told Fox News Latino. “The general sentiment in Colombia needs to express itself, but that is difficult to do.”

While the “No” vote won on Sunday, only 37 percent of Colombians eligible to vote showed up to cast a ballot – a further sign to some analysts that Colombians' enthusiasm for the ambitious accord was lacking – and to gauge the true opinion of Colombians, Sabatini said, there needs to be a better way to poll the people’s will.

“We’re seeing a fundamental problem with the plebiscite,” he said. “It’s shocking that so few people showed up to vote about something that has defined Colombian life for decades.”

Exit polling showed that the “No” vote was overwhelmingly popular with urban voters, who were being leaned on to pay for the peace largely. On the flip side, rural areas that have been hardest hit by the conflict overwhelmingly endorsed it. In the northwestern Colombian town of Bojaya, where a FARC mortar attack on a church killed dozens of civilians in 2002, the “Yes” vote won with 96 percent of the vote.

The loss for the government was even more shocking considering the huge support for the accord among foreign leaders, who have heralded it as a model for a world beset by political violence and terrorism. Many heads of state as well as U.N. Secretary-General Ban Ki-moon and U.S. Secretary of State John Kerry were present when Santos and FARC leader “Timochenko” signed the deal less than a week ago in an elaborate, emotion-filled ceremony.

With the outlook uncertain, there are a few options for Santos if he wants to pass a peace deal to be implemented before his term in office is up in 2018.

One option would be to reopen negotiations, something he been urged to do by the opposition and had ruled out in the past year. His chief negotiator said going back to the drawing board would be "catastrophic."

President Santos could also seek to bypass the vote and ratify the accord in Congress or by calling a constitutional convention.

"I've always believed in a wise Chinese proverb, to look for opportunities in any situation. And here we have an opportunity that's opening up, with the new political reality that has demonstrated itself in the referendum," Santos said Sunday night at the presidential palace.

Experts argue that if Santos, who is deeply unpopular, reopens negotiations with the FARC he will first have to work alongside his political opponents – namely former President Alvaro Uribe – to bring to the table a deal that would be favorable to the majority of Colombians.

An angry Uribe led the grass-roots campaign against the accord with none of the government's huge PR machine.

“The idea that this specific deal will be reopened is something that won’t happen,” Adriana La Rotta, a columnist with Colombia's El Tiempo newspaper and the media relations director for the Americas Society/Council of the Americas, told FNL.

Bringing Santos and Uribe together actually might be harder than achieving peace with the FARC, many say. Santos served as Uribe’s defense minister, when they worked together with the U.S. to drive the FARC to the edge of the jungles, but the two haven't spoken for years and frequently trade insults. Santos did however extend an invitation on Monday to Uribe to meet for discussions about how to move forward. It is unknown if Uribe has accepted the invitation.

Despite the uncertainty, experts say that Colombians advocating for peace can take heart in the promise by the FARC that they will continue to honor the cease-fire with the Colombian military and vowed to continue to work toward a peace agreement.

“The number one positive element to come from this vote is that the cease-fire still holds and that the FARC have reaffirmed their commitment to peace,” La Rotta said.

The Associated Press contributed to this report.