Profile: Leading candidates in Peru's presidential race

Peru is set to hold a nationwide election on Sunday to elect a successor to outgoing President Ollanta Humala, while polls show the race may head towards a runoff, as none of the contenders is expected to secure an outright victory in the first round.

The following is a brief introduction to the three leading runners in Peru's presidential race:

Keiko Fujimori, of Peru's Fuerza Popular (FP) party, leads with 33 percent of the voter preferences according to a poll by the world leading opinion poll agency Ipsos.

Fujimori is the daughter of Alberto Fujimori, Peru's former president (1990-2000) who is now serving a lengthy prison term for crimes ranging from corruption to ordering killings.

Born on May 25, 1975, Keiko Fujimori won a degree in Business Administration from Boston University in 1997 and a doctorate in the same field from New York's Columbia University in 2004.

When her father fled Peru and went to Japan in 2000 amid a corruption scandal, she was investigated for suspected illicit enrichment and other crimes, but cleared of any wrongdoing.

In 2006, Keiko was elected to the Congress, representing the capital city of Lima, and in 2010 she helped found the FP and became its leader.

She lost the presidential runoff to Humala in 2011 by a small margin.

Peruvian economist Pedro Pablo Kuczynski, of the Peruvians for Change party, is polled at the second place in the presidential race with around 16 percent of voter preferences.

Kuczynski, born in Lima in 1938 to a family of well-to-do immigrants,

studied Economics at Oxford University in Britain, and obtained a master's degree from Princeton's Woodrow Wilson School of Public and International Affairs.

Kuczynski began his political career in 1966 when he worked for the government of then President Fernando Belaunde Terry as an economic adviser. He was later appointed the general manager of the Central Reserve Bank of Peru.

In 1968, following the military coup of Juan Velasco Alvarado, Kuczynski was accused of illegally paying out money to the U.S. International Petroleum Company (IPC), and fled the country.

Living in the United States for many years, he worked for several international companies, including Magma Copper, Toyota Motor Corp., Credit Suisse First Boston and Southern Peru Copper Corporation.

Kuczynski returned to Peru when Belaunde was re-elected, and also served in the cabinets of other administrations in the early and mid 2000s.

Kuczynski ran in the presidential election in 2011 as the candidate of a four-party alliance, and came in third.

Veronika Mendoza, of the Broad Front (FA), a coalition of left-leaning parties, is polled at the third place with around 15 percent of voter preferences.

Born in 1980 in Peru, Mendoza is the youngest candidate in the race.

She has dual nationality. She ventured into politics in 2009, joining the ruling Nationalist Party (PN) and serving as a press liaison for youth and women's groups.

In 2011 general elections, she was elected to the Congress, representing the PN, but quit the party shortly after two demonstrators protesting mining pollution in her home province of Cusco were killed.

Protecting the environment is a key pledge of Mendoza's campaign. Endi