Sonia Gandhi, widow of Rajiv, the former Prime Minister, appears set to become India's first foreign-born leader after one of the most dramatic political upsets since Indian independence. Nick Meo reports from New Delhi.

Will Mrs Gandhi be the new Prime Minister?

Probably, but it is not assured yet because her Congress Party may not get the majority it needs and might need to form a coalition. Should this happen, certain left-wing parties, such as the communists in West Bengal, might put forward an alternative candidate. These groups oppose installing a foreign-born leader.

Mrs Gandhi is at a political disadvantage because she was born in Italy, which many Indian politicians do not like. She is also Roman Catholic.

While there is no constitutional problem with a foreign-born prime minister, there was a xenophobic edge to the election campaign of the ruling Bharatiya Janata Party (BJP).

The baiting of Mrs Gandhi was at times quite personal and even non-BJP supporters have some reluctance about seeing Mrs Gandhi as the new prime minister.

Also, the result is so wildly unexpected that it needs to be treated with a degree of caution until the official results are made public, which could happen later today.

Unofficial results suggest it is the biggest upset since Indira Gandhi, Sonia's mother-in-law, was voted out of office in 1979.

Sonia's son, Rahul, is also standing to become an MP and looks set for a ministerial post if he wins his seat. Her daughter, Priyanka, who has been campaigning for her mother, is also tipped to run for office one day.

Why has Congress triumphed?

It appears that the BJP made a huge tactical error by choosing to hold a snap election six months earlier than expected, in the hope that it could cash in on the popularity of Atal Behari Vajpayee, the Prime Minister.

Many have said that the result reveals the yawning gulf between India's urban middle classes and its rural poor. The BJP ran its campaign under the slogan "India is shining", lauding the country's economic growth, its burgeoning telecoms industry and other achievements.

Yet this meant nothing to the millions of rural poor who have played no part in this economic success story, and who instead struggle to gain access to clean water, food and electricity.

How was the election conducted?

More than 350 million Indians turned out to vote in the world's largest democratic elections. Nonetheless, voter turnout appears to have been quite low, with around 5 per cent fewer votes cast than in the last elections in 1999.

This year's election was a fairly complex procedure, being held over a three-week period in five stages and therefore allowing security forces to move around the country to ensure trouble-free voting.

The election has been relatively peaceful by Indian standards. Only four parliamentary seats out of 543 will have to re-run polling due to violence and problems with the electronic voting machines.

These devices promised to provide protection against the kind of electoral fraud that has beset previous elections. The high-tech system was a marked departure for India's poorer voters, many of whom are used to marking their ballot papers with their thumbs.

What policy changes will the new government bring?

Mrs Gandhi is likely to be less enthusiastic about the economic modernisation programme championed by the right-wing BJP. This plan has attempted to dismantle the system of "Licence Raj", which, it is claimed, has stifled enterprise.

The peace process between India and Pakistan is set to continue. There could be problems however, if a coalition proves to be unstable.

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