Patna: Bihar's Chief Minister Nitish Kumar was on Wednesday poised to lead his Janata Dal-United (JD-U) and its ally Bharatiya Janata Party (BJP) to an emphatic win in the assembly elections, crushing long-time foe Lalu Prasad and wiping out the Congress in one of India's most populous states.

Reaping the harvest of his widely-hailed development plank of the past five years, trends indicated that the ruling combine would sweep 199 of the 243 seats in the assembly, stunning friends and foes alike.

While a shocked former chief minister Lalu Prasad remained shuttered at his home, a bruised Congress congratulated the chief minister and pledged to introspect after indications that it would win only seven seats - less than the nine it had in the outgoing assembly.

BJP leader Arun Jaitley called the verdict a victory for 'meritorious leadership over dynastic politics' - referring to Congress chief Sonia Gandhi and her son Rahul Gandhi who campaigned extensively in the state calling Nitish Kumar a failed chief minister.

Wild celebrations erupted in the offices of the JD-U and BJP both in the state capital Patna and in New Delhi. Party activists burst crackers, beat drums and danced to victory songs.

Although both the JD-U and BJP, who have been aligned since 1996, made substantial gains over their 2005 strength, leaders of both credited the win largely to the charisma of Nitish Kumar, whose past is rooted in the country's now virtually defunct socialist movement.

The ruling alliance made substantial gains all across the state, decimating Lalu Prasad's Rashtriya Janata Dal (RJD) and the Lok Janshakti Party (LJP) of Ram Vilas Paswan even in some of its known bastions.

The RJD and LJP, which had vowed to unseat Nitish Kumar, were likely to end up with about 30 seats, dealing Lalu Prasad and Paswan - who until a few years ago were considered kingmakers in national politics - a terrible blow.

With officials starting the counting of an estimated 28 million votes polled from October 21 to November 20 at 8 a.m. across 42 centres on Wednesday, Nitish Kumar got an undisguised thumbs-up.

In the process, some of the RJD and LJP stalwarts were routed. Even RJD star and former chief minister Rabri Devi, Lalu Prasad's wife, was trailing in both the constituencies she contested.

"We are happy and celebrating," BJP leader Sanjay Jha told IANS in Patna. Added his colleague Giriraj Singh: "Nitishji will be the chief minister again."

BJP's most prominent Muslim face, Shahnawaz Hussain, said the people had embraced the development programmes of Nitish Kumar and his own party. These included building an extensive network of roads and bridges in the state where none existed, strengthening the state's educational and health sectors, and providing various incentives to the disadvantaged.

"It is clear that people have voted for development and not for caste," Hussain, a former central cabinet minister, said. He added that the result would prove to be a watershed in Indian politics.

In New Delhi, BJP spokesman Prakash Javadekar said: "People voted for an alliance that brought development as well as law and order to Bihar."

He said the loser was RJD's "15 years of jungle raj" - referring to the long rule of Lalu Prasad and Rabri Devi.

Lalu Prasad's residence in the heart of Patna was deserted, its green gates firmly shut. Barring a handful of party leaders who quietly entered the house, the only people camping outside were journalists.

A dejected Congress meekly capitulated.

"We would like to congratulate Nitish Kumar," party spokesperson Jayanthi Natarajan said in New Delhi.

She said the Congress would analyse what went wrong with its election strategy in Bihar, where the party has steadily lost influence over the last few decades.

One Congress leader, who did not want to be identified, admitted that Rahul Gandhi had not clicked in Bihar. "Rahul failed to attract voters," he said.

After the end of the sixth round of voting on Saturday, exit polls predicted a sweep for the JD-U and BJP, which took office in 2005. At that time, Lalu Prasad had rubbished the exit polls.