The Philippines has only one round of voting, unlike many countries such as France, where there is a second ballot between the two most popular candidates. This means that whoever is in front at the end of counting will become president -- no matter how small their total share of votes.

In a tight race, the prize could go to anyone. And the stakes are high.

With China and the US increasingly treating the Indo-Pacific as a staging ground for their global showdown, the Philippines will likely come under growing economic and geopolitical pressure, particularly as a claimant to part of the South China Sea.

Not only that, but his daughter -- Davao Mayor Sara Duterte-Carpio -- still has a month to decide if she'll run for president as a substitute candidate.

Duterte has a personal incentive to retain some control over the future government: he's facing an investigation by the International Criminal Court into his war on drugs and his successor could influence how much access they get to the Philippines.

"We're at the edge of a cliff ... whoever wins will determine whether we'll have rule of law, whether our economy can grow, whether we can survive the virus, whether our society can heal," she said.

The dictator's son

Marcos Jr., known colloquially as "Bongbong," announced he would run for president in the 2022 election, pitching himself as a unifying candidate who could bring the country together after the ravages of the Covid-19 pandemic.

"The Marcoses remain scot-free from jail, they haven't returned all the money that they got from the nation's coffers, and now they are making a comeback for the highest position in the land. That is just plain, shameless gall," Cristina Palabay of rights group Karapatan told Reuters.

Duterte has not been ashamed to tie himself to the Marcos family. There were even suggestions he might join Marcos Jr.'s ticket as candidate for vice president. "That's the plan!" Marcos Jr. said Wednesday, according to ABS-CBN.

Ressa said Duterte's popularity in the south of the Philippines, combined with Marcos' popularity in the north, would create a formidable force.

Heydarian added the Marcos family had "grassroots support, resources and message discipline," but their history would not play well with a population concerned about corruption.

"The issue of corruption is very, very sensitive for a lot of people," he said.

The boxer

Pacquiao's skill as a boxer is unquestionable. After a 26-year career, he is considered one of the greatest boxers of all time, the only man to hold world titles in eight different divisions.

But the 42-year-old's skill as a politician is far less clear -- and something he will have to prove if he is going to be successful when he runs for president.

But Heydarian said since he joined the senate, Pacquiao's time in office has been underwhelming. "He's entering this race as someone whose mantle of statesmanship is still under question. He didn't have the most impressive performance as senator," he added.

Rather than running for vice president first, to show he was serious about the role, Pacquiao has jumped straight to the top job -- and Heydarian said that might be a bit "early" for people. Still, his popularity with the country's poor could make him a contender.

Ressa said the Philippines will need urgent action to recover from the Duterte years and the Covid-19 pandemic, and questioned whether Pacquiao had the political coalition or the governing experience to make it happen.

"Whoever will become president next will have real problems to deal with, and they're going to have to have competent people to deal with it," she said.

The actor

Pacquiao isn't the only rags-to-riches story of the 2022 campaign -- nor the only star.

In fact, Moreno's real name is Francisco Domagoso -- Isko Moreno is his stage name.

Using his reputation as a stepping stone, Moreno moved into politics in 1998 as a city counselor in Manila before being elected vice mayor in 2007, and then mayor in 2019.

Just two years after his win, he is aiming to lead the entire country. Like Duterte, Moreno is a populist, Heydarian said, but one of a different stripe.

"(He) represents what I call 'polite populism': cost-free, family orientated, even pious kind of rhetoric," he said, adding that Moreno trumpets centrist and even at times progressive policies.

The Vice President

At the other end of the spectrum from Marcos is incumbent Vice President Robredo.

Accompanied by her two daughters, Robredo on Thursday called for the country to follow her and help "ensure a future of equal opportunities."

Heydarian pointed out that Robredo is currently running fifth in the polls despite her national reputation -- behind Marcos, Pacquiao and Moreno.

However he said the Vice President had a wide network of supporters across the country from her time in office. "We saw in the 2016 (Vice Presidential) election she was able to turn things around against all odds and against a very competitive candidate," Heydarian added.

The shadow of Duterte

While the country's attention has largely been fixed on the candidates who have already declared, none of them are leading recent polls, according to Heydarian.

He said the most popular contender is Duterte-Carpio, Duterte's daughter.

As of Friday, Duterte-Carpio had not declared her candidacy but instead has filed paperwork to run again for Davao mayor. On Monday, her spokesman said she had "no intention" of taking the leadership of her father's party.

That's exactly what her father did in 2016.

Heydarian said Duterte-Carpio isn't like the President in many ways -- she welcomes the opinion of experts and takes considered decisions, unlike her impulsive father.

But critics have seen her potential candidacy for president as another way for Duterte to hold sway over the Philippines after he leaves power.

And that is assuming her father doesn't change his mind about running for vice president. Ressa said she doesn't trust Duterte's statement that he would retire from politics -- he said the same thing in 2016 and then ran for the country's highest office.

Whoever ends up taking power in the Philippines, Ressa said they will inherit a country "in a far worse place" than Duterte did.

"The legacy of Duterte is the breakdown of the different branches of government and the corruption of the different weak institutions," she said.

"We were just at the point where our institutions were starting to solidify ... the last five years have really taken those dreams and dashed them."