But the winner of next month's election seems a foregone conclusion, because KR Narayanan has won the endorsement both of the ruling United Front and the Congress Party. If he wins, this former diplomat and graduate of the LSE will become the first member of a "scheduled caste" - the first Untouchable - to hold India's highest office in the nation's 50-year history.
Kocheril Raman Narayanan's career is a demonstration both of how India's caste barriers can be transcended, but also of the powerful grip they still retain on Hindu thought. Raised in the state of Kerala in the far south, Narayan is a Paravan, a lowly group whose traditional vocation was picking coconuts. Both his father and grandfather were ayurvedic doctors in the region, administering natural remedies for very little money. As a child he was forbidden even to walk past the houses of high-caste villagers, as even today his brethren are banned from entering temples or using the high castes' wells.
Narayanan himself, though graduating top of his year at university, was offered nothing more flattering than the post of college clerk. A beaming, mild-mannered character, with the looks of an Indian Betty Boothroyd, he survived this rebuff and after a spell in journalism gained a scholarship to the LSE. Armed not only with a degree in economics but also with a letter of recommendation from Harold Laski to Nehru, he was speedily inducted into the diplomatic service, and has travelled the world as envoy and ambassador.
Delhi's press is saturated with tales of political corruption, among which the news of Narayanan's candidacy surfaced with lotus-like purity. Mr Narayanan "has everything that the high office demands," said the Hindustani Times, in a typical comment, "...high personal integrity, dignity, scholarship and grace." But such a description would also apply to the incumbent, SD Sharma, a freedom fighter before independence and a Cambridge law graduate, who has exercised considerable shrewdness and wisdom during his five-year term.
Somehow the office of President, tainted during the Gandhis' years (1966 to 1989) when successive presidents bowed the knee to the Prime Minister, has managed to claw back its original esteem, its claim to being "keeper of the nation's conscience."
Some cynics here profess themselves disgusted by the politically-correct complexion of Mr Narayanan's candidacy. "By condescendingly ... choosing him," fumed the Indian Express, "they pretend to have upheld the social conscience...of the nation."
As compensation for centuries of dire injustice, one presidency doesn't amount to much. But if Mr Narayanan can build on the acclaim with which his candidacy has been greeted and go on to do something about the stink arising from Indian politics, his nation will be grateful.