Should Narendra Modi actually be crowned the prime minister in May, the post-Mandal social justice political platform will finally have prevailed at the centre too. Egalitarianism will have trumped the caste/class stranglehold on Delhi Durbar. The "chaiwala" jibe will reverberate with great irony, but only if Modi has the numbers to obstruct the concert of regional leaders.

A gradual erosion of the caste or feudal hierarchies has been taking place since independence in the south, west and eastern India. After Narayan Dutt Tewari and Jagannath Mishra surrendered their chief ministerial bungalows in Lucknow and Patna respectively in 1989, these stations too are firmly with backward caste and Dalit leaders.

The Gaddi at Delhi has so far been insulated from the winds of change. Of the 66 years since independence, Delhi has been ruled by Brahmin prime ministers for 51 years, including spells of six years by BJP's Atal Bihari Vajpayee and two-and-a-half-year of Janata Party's Morarji Desai.

Manmohan Singh's 10 years must be considered unique because it is unlikely that there will be a Congress president as powerful as Sonia Gandhi was in 2004 when she nominated him the prime minister. Sonia did have a nebulous, Brahmin afflation but Manmohan Singh was outside the caste framework.

Lal Bahadur Shastri, Charan Singh, V.P. Singh, Chandra Shekhar, H.D. Deve Gowda and Inder Gujaral together account for about four years.

The evidence so far shows that it has not been possible to forge a durable consensus on a caste other than the Brahmin for the job of prime minister of India. A Kayastha, two Rajputs, a Jat, a Vokaligga and a Khatri became prime ministers but did not last beyond a year or two. Every Brahmin prime minister completed his term.

The question of a non-Brahmin alternative at the centre never arose for the 38 or so years that the Nehru-Gandhi family lasted at the helm. Dynasty ensured continuity.

P.V. Narasimha Rao was the first Congress prime minister who faced, with great anxiety, the prospect of Brahmins losing political power. He himself came on top under unusual circumstances.

Had Rajiv Gandhi not been assassinated half way through the 1991 general elections, he would probably have had to sit in the opposition. A wave of sympathy after his death gave Narasimha Rao just the number of seats from the south to be able to hold onto power with his cunning and craft. He never allowed a rival power centre in the Hindi belt to emerge. Arjun Singh was assiduously kept out. This made room for the BJP to grow.

The 1991 verdict taught the Congress a lesson: the electorate was discarding Brahmin candidates. Satish Sharma, Sheila Kaul, Mani Shankar Aiyer and Vidya Charan Shukla were the only winners.

This trend was not confined to the Congress. If stalwarts like Vasant Sathe and V.N. Gadgil lost in Maharashtra, so did the opposition's Madhu Dandwate and Rama Krishna Hegde lose, the latter from Karnataka.

Narasimha Rao was quite transparent with his preferences. Three of the four Brahmins who won elections were slotted in the cabinet. Others like Pranab Mukherjee, Bhuvanesh Chaturvedi, V.N. Gadgil, Nawal Kishore Sharma and Jitendra Prasad were accommodated variously, in the Planning Commission, Rajya Sabha and as party general secretaries and spokesmen of the party.

Traditionally, the vice president became chairman of the Indian Council of Cultural Relations. Narasimha Rao bypassed K.R. Narayanan and handed the job to Vasant Sathe who had lost from Maharashtra. For similar consideration, Gen. V.K. Krishna Rao was retained as governor of Jammu and Kashmir for an exceptionally long tenure despite the controversies attending him.

I am citing these details not as proof of the Brahmin's assertiveness but as evidence of his tenuous hold on political power and general nervousness that even this was receding from him.

Narasimha Rao would have been quite content when Atal Bihari Vajpayee became the prime minister in May 1996 but this government lasted just 13 days. After a turbulent two years of Deve Gowda and Inder Gujaral, Vajpayee came back as leader of the National Democratic Alliance for full six years, an extra year on account of the circumstances in 1998-99.

The 2004 election results were a shock, in different ways, for Vajpayee and Sonia Gandhi. The act of renouncing power raised Sonia Gandhi's stature sky high even though, it must be added in parenthesis, she did not have much of an option. If she had listened to the wailing, weeping party loyalists and yielded to the temptations of prime ministership, the issue of her "foreign origin" would have plagued her.

The most capable Congress leader available to her for the top was Pranab Mukherjee. But he would have had considerable political potential beyond her control. Manmohan Singh was a tried economist, well in tune with the "sole" superpower, and would not be a political threat just in case Rahul Gandhi readied himself for battle.

Assuming that Rahul Gandhi has his eyes set on a vague future beyond 2014, the only certainty in the coming elections is that the BJP will be the largest single party.

Unlike the Congress, the BJP has shown greater foresight in opening the option of a social justice route to power. Kalyan Singh, Bangaru Laxman, Uma Bharti are some examples. There clearly are in the Sangh Parivar lobbies for and against this trend. Hence the periodical waxing and waning of these stars. But nothing succeeds like success, and Madhya Pradesh Chief Minister Shivraj Chauhan is an example of the Parivar's endorsement of the trend.

Prime Ministership is a different level of play. Should the party win an adequate number of Lok Sabha seats, the RSS-BJP leadership's commitment to social justice will also be seriously on test.

A senior commentator on diplomatic and political affairs, Saeed Naqvi can be reached on saeednaqvi@hotmail.com. The views expressed are personal.