The world's largest democracy yesterday delivered one of the biggest electoral shocks in Indian history. Almost everybody in India, most notably Atal Behari Vajpayee, its outgoing prime minister - who brought the elections forward by six months to capitalise on booming economic growth - failed to detect the warnings.

Most of India's pollsters forecast either a narrow victory for the BJP-led multi-party coalition or a hung parliament tilted in Mr Vajpayee's favour. Even the exit polls by New Delhi Television, consistently the least inaccurate of forecasters throughout the election, predicted the ruling coalition would only fall short by 20 to 40 seats.

In the event, the BJP-led coalition fell more than 80 seats short of the half way mark of 272.

How could everybody be so wrong? "If you look at how journalists and even pollsters operate, they go to the small towns and think they've landed in the real India," said Mala Singh, editor of Seminar magazine in Delhi, one of the few people to predict the outcome. "But even the smallest, most out-of-the-way town, is a long way from the villages where most of India lives."

Yesterday, India's impoverished villages - and large swathes of its cities, where urban slum dwellers also came out in droves - gave educated and metropolitan India a reminder of the country's vibrant democratic undercurrents.

The verdict, which has put India's ruling Nehru-Gandhi dynasty back in the driving seat two decades after its last electoral victory, is likely to have profound effects.

"The first priority of the new government and of any government in India must be to tackle rural poverty and backward agriculture," said Manmohan Singh, a Congress leader seen by some as a possible consensus prime minister if, as seems decreasingly likely, Congress allies object to Sonia Gandhi's leadership. "This is the inescapable lesson of the election."

With 149 seats, Congress will dominate the new coalition. But the outcome is not a ringing endorsement. Yesterday the Congress-led government of the southern state of Karnataka - of which Bangalore, the booming software city, is capital - was swept out of power by the opposition BJP in an assembly election.

Most Congress members of parliament from Kerala, another southern state also ruled by Congress, were yesterday defeated by their main state-level opponents in the Communist Party of India (Marxist).

India's voters are dismissing governments wherever they find them. "Congress should be aware of the fact that the Indian voters have not voted for anybody - they are rejecting everything in sight," said Sundeep Waslekar, an analyst. "This is a cry of impatience for corrupt and self-serving politicians to finally start delivering the goods."

In a recent survey, Mr Waslekar estimated that more than 80 per cent of India's 1.05bn people lived in the "bullock cart economy" - without even the means to afford a bicycle. Another 15 per cent lived in the "two-wheeler" economy. They could afford scooters and televisions. And only two per cent - about 25m people - inhabited the "business class" economy, those who can afford to fly and to dine in restaurants.

"The BJP's whole election campaign of 'India Shining' was targeted at the booming urban elites," said Dilip Cherian, head of PerfectRelations, an agency that worked for Congress. "We chose to ignore it altogether and disseminate low-key material in 48 rural areas that we had previously identified as important." Mr Cherian said the BJP outspent Congress by a multiple of five with an estimated $100m campaign budget.

But much of the BJP's glitzy advertising either failed to reach inhabitants of the bullock cart economy, or if it did, simply galvanised their rebellion in the privacy of the polling booth.

"Today - for the first and last time - I am grateful so much of India is illiterate," said a prominent social activist who did not want her name published. "It was the literate middle classes that fell victim to the BJP's propaganda. And it is the poor who have corrected their misperceptions."

But there is another lesson that many are drawing. In its manifesto, Congress described the contest as one between a party that saw India as a pluralist and modern nation and the BJP that stood for "the forces of obscurantism and bigotry".

In the BJP's campaign, leaders such as Mr Vajpayee and L.K. Advani, the hardline deputy prime minister, played down the BJP's Hindu nationalist ideology. Both men were photographed wearing Muslim headgear and talked frequently of Hindu-Muslim unity. Muslim voters, almost 14 per cent of India's electorate, are disproportionately poor and illiterate. But electoral analysts said they had voted in a consistently pragmatic way. "Wherever the BJP candidate looked like winning, Muslims voted tactically for the strongest opponent," said Yogendra Yadav, a leading analyst. "They were voting for their own security."