India’s ruling Bharatiya Janata Party led by Prime Minister Narendra Modi appeared to set taste today of its first defeat in a state legislature poll since sweeping to power last year as counting of votes for Delhi assembly picked up pace showing a resurgent anti-corruption party on track to register a landslide win.

Self-proclaimed “anarchist” Arvind Kejriwal-led Aam Aadmi Party (AAP) established a huge lead in early trends in the counting of votes for all the 70 seats in Delhi assembly -- crossing the halfway mark, while its main rival BJP was lagging behind.

According to leads of state-run Rajya Sabha TV, AAP was ahead in 36 seats among 56, out of the total 70 seats. BJP was ahead in 15 and Congress in four, reports our New Delhi correspondent.

According to leads from other TV news channels, AAP had made gains in 16 seats when compared to the last assembly polls in the Indian capital in 2013. BJP, on the other hand, was trailing with 12 seats it had won in the last elections.

NDTV projections gave AAP a total of 45-50 seats, more than two-thirds of the majority. If that happens, AAP will have marked a tremendous improvement in its seat tally of 28, which the party had won less than two years ago when BJP had emerged as the top party with 31 seats but fell short of majority.

Congress party, led by Sonia Gandhi, which was voted out of power by BJP in India in the parliamentary elections in May last year, had secured just eight seats in Delhi assembly elections in 2013 and is expected to get even less this time.

Sharmistha Mukherjee, candidate of the party from the greater Kailash constituency of Delhi, may see defeat at the end of result of the elections.

The setback for BJP came at a time when Modi needed to win most of the state legislature elections over the next four years to gain control of both Houses of parliament to deliver on his promise of jobs and economic reforms in legislations and growth.

The upper house Rajya Sabha, where BJP is in a minority, is frustrating in its efforts to pass laws related to tax and foreign investment.  A defeat for Modi's BJP in Indian capital could affect his chances of consolidating power in parliament where his economic reform agenda is being thwarted by the opposition.

BJP had fielded  its top national and state leaders to campaign for the high-profile Delhi assembly election and Modi himself took out full-page advertisements on the front of several major newspapers in the capital on Friday in a last-minute effort to sway voters.

BJP, which under Modi won India's biggest election mandate in three decades last May, won three of the four state legislature elections in Maharashtra, Jharkhand and Haryana over the past year. However, AAP seems set to halt BJP’s juggernaut in Delhi.