PENPIX - Key politicians in India's general election

Chief of India's ruling Congress party Sonia Gandhi speaks during the release of Congress party's manifesto for the April/May general election in New Delhi in this March 24, 2009 file photo.

Reuters - The following are profiles of politicians who will play a major role in the April/May general election that gets underway this week.

SONIA GANDHI, Ruling Congress party president: Considered India's most powerful politician, the 62-year-old remains the party's crowd-puller who gave up the chance to become prime minister in 2004 in favour of party colleague Manmohan Singh.

The gesture earned the torchbearer of the Nehru-Gandhi dynasty respect among many Indians as a selfless politician. She is the widow of former Prime Minister Rajiv Gandhi.

Once voted the world's sixth most powerful woman by Forbes, Gandhi helped craft two of the government's most important policies: the National Rural Employment Guarantee Scheme and a loan waiver for farmers, underlining her left-of-centre stance.

PRIME MINISTER MANMOHAN SINGH: Congress's prime ministerial candidate. The father of India's economic reforms, Singh's image of a compromise prime minister opened him up to criticism that he took orders from party boss Gandhi and he has been criticised as a weak and directionless leader.

He regained stature by pushing through a civil nuclear deal with the United States, despite opposition from his left allies. Singh, 76, takes a keen interest in economic issues -- a rarity in India where prime ministers focus mostly on foreign affairs and domestic politics.

LAL KRISHNA ADVANI, Main Hindu-nationalist opposition's prime ministerial candidate: Variously described as a hardliner, a hawk and a wily politician, Advani is a leading advocate of his Bharatiya Janata Party's (BJP) trademark Hindu revivalism.

Born in Pakistan when it was a part of undivided India -- he is hawkish about ties with Islamabad -- the 81-year-old is more of a career politician than technocrat.

When Advani's own coalition government was in power in 1999-2004, it pushed pro-market reforms including privatisation of state-run companies.

PRAKASH KARAT, General Secretary, Communist Party of India (Marxist): The communists have strongholds in three Indian states from where they usually win enough seats to hold the balance of power in a hung parliament. Karat is their ideological hardliner.

He is uncompromising in his opposition to India's growing ties with the United States. Any government propped up by his party will find it difficult to push economic reforms.

MAYAWATI, Chief of Bahujan Samaj Party: A caste-based politician known as the "Queen of the Dalits", Mayawati, who uses only one name, has emerged as a strong political force.

Based in Uttar Pradesh, Mayawati, 53, has prime ministerial ambitions and she has played an important role in gathering opposition to the government. Her party won a majority in the state election in 2007. If Mayawati does well, it could cast doubt on what economic direction a future government with her would take and further entrench caste politics nationally.

Mayawati is also controversial, with a history of corruption allegations against her.

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