Mindanao, Philippines - Close to 55 million voters have started casting their ballots in the Philippines' presidential election which could, for the first time, propel a politician from the southern island of Mindanao to power.

This could signal a turn away from the policies of President Benigno Aquino and the political centre in the capital Manila.

Polls opened across the country at 6am local time on Monday (22:00 GMT Sunday) and the election pits frontrunner Rodrigo Duterte, an outspoken mayor from the city of Davao, against four other contenders.

Duerte's strongest challenger is Grace Poe, a freshman senator who is weighed down by questions about her previous US citizenship.

Another candidate, Manuel Roxas II, a former senator backed by Aquino, is battling anti-establishment sentiment, while Jejomar Binay, the current vice president, is facing corruption allegations.

Senator Miriam Santiago, a fifth candidate, barely registers in the polls.

Duterte, who has faced allegations of human rights abuses and hidden wealth, has anchored his campaign in the fight against crime and corruption in the country.

He said he would declare a "revolutionary government" if criminality is not solved within the first six months of his presidency.

The promise, however, raised concerns in the business community and among other political observers, who have warned against the return of an autocratic rule similar to the time of Ferdinand Marcos 30 years ago.

But Duterte has endeared himself to voters with his plain, often expletive-laden talk which has got him in trouble on a few occasions including the time he cursed Pope Francis, made jokes about rape and threatened to burn Singapore's flag.

He also railed against the economic gains during Aquino's six years in office, which he said failed to trickle down to the masses.

Myrish Cadapan-Antonio, a Filipino lawyer and professor at Harvard's Kennedy School, told Al Jazeera that Duterte's rise reflects "a deep-seated angst among the masses for trickle-down development" and a "united" southern vote against "Imperial Manila".

Antonio said there is also deep frustration among voters both towards the system of government and the current administration.

"It is difficult to discern who or what the object of such anger is but it is very evident," she said, pointing to the "passion" of Duterte's supporters towards their candidate.

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But whoever wins the presidency has to face the reality of a system of government dominated by political dynasties, including Duterte, who is a son of a former governor, said Earl Jude Cleope, a professor of history and education at Silliman University in central Philippines.

"If you look at it now, traditional politics is still at work, and it is still crucial in delivering the votes for the eventual winner," Cleope told Al Jazeera.

Gina Balios, 18, and a single mother of a five-month old son, said she hopes the next president will work hard to give more opportunities to poor Filipinos like her.

"I don't think I will ever get a chance to finish college. But I hope my son will, someday," Balios told Al Jazeera.

Before the polls opened, President Aquino issued a statement on Sunday calling on Filipinos to exercise their right to vote, while urging a "peaceful" and "orderly" process reflecting "the spirit of democracy".

Aside from the race for president and vice president, there are 18,000 national and local positions being contested in the polls, attracting the candidacy of 44,000 individuals.

Follow Ted Regencia on Twitter: @tedregencia