In pictures: India's election campaign

Supporters of Narendra Modi, the prime ministerial candidate for India's main opposition BJP, wear masks of their leader during a rally being addressed by Mr Modi in Chennai.

India's political parties are campaigning for general elections in April and May. The vote pits the governing Congress party-led coalition against the opposition BJP and its allies. The BJP is led by the charismatic and controversial Hindu nationalist leader, Narendra Modi, masks of whom are seen being worn by supporters above.

Rahul Gandhi of Congress party greets supporters during an election rally at Balasinor in the western Indian state of Gujarat.

Congress is being led by Rahul Gandhi, the latest member of India's influential Nehru-Gandhi dynasty. Manmohan Singh, who has been prime minister for the last two terms, is stepping down.

Leader of Aam Aadmi Party, or Common Man Party, and anti-corruption activist Arvind Kejriwal, center, greet supporters during an election rally in Ahmadabad.

A new anti-corruption Aam Aadmi (Common Man's) Party (AAP) will also contest the elections. Led by activist-turned-politician Arvind Kejriwal, the AAP made a spectacular debut in state polls in Delhi last year.

A cyclist rides past pictures of Tamil Nadu state chief minister and All India Anna Dravida Munnetra Kazhagam (AIADMK) leader Jayaram Jayalitha on the party symbol, two leaves displayed on a wayside in Chennai.

If no single party wins a clear majority, smaller parties like the AIADMK, led by J Jayalalitha, could play a crucial role.

Supporters of Narendra Modi, the prime ministerial candidate for BJP during a live video broadcast campaign on "Talk over tea with Modi", in the northern Indian city of Chandigarh.

Mr Modi, who is ahead in all the opinion polls, is the chief minister of Gujarat state which witnessed some of India's worst anti-Muslim riots in 2002. He has been holding discussions with people over tea, during which he lays out his vision for India and takes questions from the audience.

Indian woman stitches Congress party flags ahead of parliamentary elections in Ahmedabad.

Observers say a slowing economy, high inflation, a string of high-profile corruption scandals and a government that is perceived as jaded all mean the Congress party is likely to fare badly at the polls.

Indian village man plays a traditional wind instrument at an election campaign rally addressed by Congress party vice president Rahul Gandhi in Rajasthan.

However, Rahul Gandhi's public meetings have still been drawing crowds - including supporters like this village man playing a traditional wind instrument at a rally in Rajasthan.

Aam Aadmi Party, or Common Man Party, supporters gather for an election rally addressed by AAP leader and anti-corruption activist Arvind Kejriwal in Ahmedabad.

The anti-corruption Aam Aadmi Party has also been drawing large crowds in some cities and could win a number of seats as well as playing the role of spoiler in others, taking votes from more established parties.

Indian workers give the final touches to election campaign vehicles bearing BJP and and Telugu Desam party (TDP) symbols and logos in Hyderabad.

Some 814 million Indians are eligible to vote at 930,000 polling stations - parties are using colourful campaign vehicles to reach out to voters.

Indian workers make BJP campaign flags at a workshop in Hyderabad.

Elections give a boost to India's economy. Here, workers make campaign flags for the BJP at a shop in the southern city of Hyderabad.

An Indian man offers prayers as he stands in front of different party campaign flags displayed at his workshop in Hyderabad.

No single party has won a majority in India's parliament since 1989 and governments since then have been formed with the support of smaller, regional parties. This election promises to be no different - although a new prime minister seems certain.