"Having said that, these exit polls ring true to the extent that they suggest yet again that India will not have a single party with a simple majority in parliament."
Neither the Congress party nor the opposition, led by the BJP, is expected to win the 272 seats necessary to secure a parliamentary majority.
Early surveys carried by India media outlets on Wednesday indicated a lead for the Congress and its allies with 37 per cent of the vote, which equals 205 seats in parliament.
The main rival, the BJP and it allies, were just behind with 34 per cent of the vote, which would give it 185 seats.
The other major political player, called the Third Front, is expected to win up to 130 seats or 23 per cent of the vote.
The counting of actual votes will begin early on Saturday, with the final tally expected to be released later the same day or early on Sunday.
In total, about 714 million voters were eligible to take part in the marathon polls, which were staggered over the course of a month for logistical and security reasons.
According to the Indian constitution, a new parliament must be in place by June 2.
The final verdict is expected to trigger a frantic round of political horse-trading as the two main blocs scramble for new partners among a multitude of regional parties, all with their own local agendas.
The Congress, which has been in power for the past five years, has seen its main achievement of a robust economic growth hit by the global economic crisis.
The party also faces severe criticism for its handling of the Mumbai attacks in November, when 10 armed men - allegedly from Pakistan - rampaged through the city, killing 166 people.
|The Indian elections are the world's largest exercise in democracy [AFP]
Nonetheless, Abhishek Manu Singhvi, a Congress spokesman, said the party was confident of forming a coalition government.
"Whether individually or collectively we know very well how to conduct coalition ethics," he said, adding that they have the necessary experience to "do it successfully".
For its part, the BJP says it is confident of wresting power and ruling the country together with its allies for the next five years.
Many of the seats are expected to go to a range of regional and caste-based parties that tend to focus on local issues and promises, leaving India facing the prospect of a shaky coalition.
Observers say that whatever formation emerges it will most likely be an unwieldy coalition that will struggle to project a united front at a time when India is facing a sharp economic downturn and numerous foreign policy challenges.