Philippine President Benigno Aquino is appealing for a peaceful, orderly vote as millions head to the polls to choose his successor and candidates for other elected offices.
Violence and fraud have been the hallmarks of past elections in the Philippines, and Aquino said it is time to show the world the country knows how to reflect the spirit of democracy.
"Despite our deep passion and support for our candidates, we can hold elections that are peaceful and orderly," he said.
Polls going into Monday's voting show the tough talking mayor of Davao, Rodrigo Duterte, as the surprise favorite. Duterte is known for his profanity-filled speeches against the government and his threats to murder criminals.
But Duterte's opponents, including Aquino, warn voters not to turn the country over to someone who they say can easily become a dictator.
Voters also are choosing candidates for 18,000 federal and local offices.
The constitution limits the Philippine president to a single six-year term. Aquino is credited with turning the Philippines into one of Asia's most thriving economies.
But his critics say most of the country's wealth is concentrated among a small number of industrialists, with the gap between rich and poor remaining extraordinarily wide.