The Philippines held elections Monday seen as crucial for President Benigno Aquino's bold reform agenda, as deadly violence and graft-tainted candidates underlined the nation's deep-rooted problems.

Aquino has called for the mid-term polls, in which thousands of local leaders plus national legislators will be elected, to be a referendum on his efforts to transform a corrupt political system and an underperforming economy.

"The president is asking voters to put their confidence in those on the administration slate to help him carry out the rest of his reform agenda," presidential spokeswoman Abigail Valte told AFP.

Aquino swept into power with a landslide election victory in 2010 on a promise to fight corruption that he blames for crushing poverty in the country of 100 million people.

Opinion polls show he remains one of the country's most popular presidents ever, with the Philippines currently enjoying economic growth faster than every other nation in the Asia-Pacific except for China.

Aquino's high-profile war on corruption, which has seen charges laid against his predecessor, Gloria Arroyo, has also won widespread support.

But, with presidents restricted by the constitution to serving just one term of six years, Aquino is in a rush to implement more ambitious reforms while making a deeper impact on graft.

The mid-term elections -- in which more than 18,000 positions, from town councillors up to provincial governors and members of the legislature, are being contested -- are vital to shore up political support for his efforts.

Most crucial is control of both houses of Congress.

Aquino is confident of securing big majorities in both houses from an alliance of a wide range of parties, enabling him to pass legislation much more easily than his first three years when he did not have control of the Senate.

One of Aquino's biggest reforms is a planned peace deal with Muslim rebels to end a decades-long insurgency in the south of the country that has claimed an estimated 150,000 lives and severely curtailed economic growth.

That peace deal would require parliamentary endorsement.

Aquino's aides have also said he is focused on passing legislation that would expand the tax base, including from the mining sector, to pay for more social security services.

Nevertheless, amid the hope, the elections also highlighted that many of the darkest traditions to have plagued Philippine politics since the end of Ferdinand Marcos's dictatorship in 1986 remained deeply entrenched.

The Philippines is infamous for a brutal brand of democracy where politicians -- particularly at the local and provincial levels -- are willing to bribe, intimidate or kill to ensure they win.

Six people were killed on Sunday, including an election monitor, bringing to more than 60 the number of fatalities in violence linked to the polls.

Meanwhile, a host of candidates with links to corruption or violence ran as candidates, highlighting a so-called "culture of impunity" in which powerful figures easily skirt around the justice system.

Among them was Imelda Marcos, 83-year-old wife of the ex-dictator, who was widely expected to win a second term in the nation's lower house representing a northern province which has for decades remained a family stronghold.

Joseph Estrada, a former president evicted in a popular uprising in 2001 and later convicted of committing plunder while in office, was running to become mayor of Manila, the nation's capital.

Two men on the run after being charged with murder, and another wanted for alleged child rape, were running for local level positions.

Reflecting sentiments across the country, voters at a Manila polling station said they would decide according to who could help them the most economically.

"I know he has a soft spot for the poor and if I need his help... I could approach him," Flordeliza Pastoral, 55, an emaciated slum dweller said of her plans to vote for Estrada.