India is tired of the Congress Party and its dominant Nehru-Gandhi dynasty and will demand sweeping changes in the general election that is due to be held in just over four months’ time. It may not however just want a switch between the established Congress and the Bharatiya Janata (BJP) parties, but could demand something new in politics that will tackle the country’s endemic corruption, crony capitalism and inefficient government.

That is the conclusion that can be drawn from election results for four state assemblies. A completely new anti-corruption party, the Aam Aadmi (common man), won an astonishing 28 of the 70 seats in Delhi, which will make it the official opposition. Congress was decimated after 15 years’ rule, winning just eight seats compared with 43 in the last election in 2008 - a humiliating result that was far worse than had been expected.

Congress also suffered a resounding defeat by the BJP in Rajasthan, down from 96 seats to 21 after five years in government. The BJP held on to power against Congress in Madhya Pradesh and Chhattisgarh. Vote counting in a fifth state, Mizoram in north-east India, is in progress today and looks like a Congress victory.

The Aam Admi Party's victory is significant because it demonstrates a desire for change and a break with the corruption and mismanagement of recent years. Its social activist-turned politician leader, Arvind Kejriwal, talks about a new sort of politics, and the party’s election symbol is appropriately a broom. Focussing on local as well as state-level issues, the party produced individual manifestos for each of Delhi’s 30 assembly constituencies as well as one for the state as a whole.

In recent months, Narendra Modi, the controversial chief minister of Gujarat and the Hindu-nationalist BJP’s prime ministerial candidate, has been campaigning rumbustiously around the country promising to provide the new style of efficient and clean government that India needs at a time of high inflation and relatively low economic growth and high inflation.

That campaigning pitch is now being challenged by Kejriwal’s party, which is offering a far more radical fresh start and style than Modi. How far it can extend beyond Delhi, where its anti-corruption campaign has been focussed, is open to question. It says it has active organisations in 22 of India’s 28 states, but it will be stretched to do well in many of them.

It will also face competition that does not exist in Delhi from established regional parties based on caste and other factors. In Delhi, it will have to show that it can transform itself from an anti-corruption movement into a working political party and play a meaningful role as the assembly's main opposition, once a new government has been installed (this is delayed because the BJP, which led in the polls with 32 seats does not have a clear majority).

The results mean that Congress and the Nehru-Gandhis are facing a massive defeat – indeed rejection - in the general election. National polls do not necessarily reflect local results, but the scale of today’s defeats does seem to indicate what will happen next year when seen against the background of the national mood of despair about the current Congress-led United Progressive Alliance coalition.

This is a disastrous setback for Rahul Gandhi, heir to the party’s leadership who, once again, has failed to move voters despite extensive campaigning. He has had earlier personal leadership failures in Uttar Pradesh and Bihar state polls. He is a reluctant politician, who gives mixed messages. On the one hand he talks about reforming his party so that new leaders emerge from the grassroots, while at the same time, along with his mother Sonia and sister Priyanka, behaving as though he and they have a dynastic right to rule. It is that right that is now being rejected.

Rahul’s grass-roots ideas could provide a credible answer to the Aam Admi, but he has not so far been able to achieve change in a party that is riven with crony patronage-oriented organisation and relationships. Speaking after Congress’s defeat, he told reporters in Delhi that political parties were “not giving adequate voice to the man in the street… and it is our job to do that”. He said that he would put all his efforts to 'transforming the organisation of the Congress Party” and would now push those changes “aggressively”. Political analysts believe that, though he will do what he can before next year’s polls, his target is to make changes by the following general election.

Who will win next year cannot yet be forecast. It could be a BJP-led coalition led by Modi, though that will depend on the BJP winning sufficient seats in India’s northern states to persuade regional parties to join a coalition led by him. Or it could be a muddled coalition supported but not led by either the BJP or possibly the Congress. That is the best that the Gandhis' party can hope for, but it would not be good for the country which needs strong economic and developmental leadership.

Although the BJP won in the four states, it did not have the resounding victory it had hoped for because of the Aam Aadmi’ s emergence in Delhi and a close-run contest with Congress in Chhattisgarh. There will now be arguments about how much Modi contributed to the successes, or whether they were due to strong chief ministerial candidates in Rajasthan, Madhya Pradesh and Chhattisgarh.

Sheila Dikshit, 71, who has been the chief minister of Delhi for the past 15 years, suffered the day’s biggest defeat because she lost her own central-Delhi assembly seat to Kejriwal, as well as losing the assembly to the BJP. She has generally tried to evade responsibility for Delhi’s significant problems in the past five years, deflecting criticism of the appalling and corrupt preparations for the Commonwealth Games in 2010 and continuing inadequate water and electricity supplies. She also blamed the police during a rape case a year ago that aroused international as well as national outrage. She is identified with the Gandhi family.

The state elections were pitched in the media as a contest between Rahul Gandhi and Modi, but Arvind Kejriwal, the outsider, has emerged as the winner with Rahul as the loser. Rahul is 43 and Kejriwal is 45 – if both have the staying power, one to transform his party and the other to build a new one, they could maybe begin the political change that India needs. Both have a huge task and could be overwhelmed by the entrenched political establishment but they have time on the side which Modi, aged 63, does not.

(John Elliott writes a Delhi-based blog http://ridingtheelephant.wordpress.com/)