NEW DELHI (AFP) - Narendra Modi's party won a landslide victory in India's most populous state on Saturday (March 11) in a massive vote of confidence for the prime minister halfway into his first term.
Modi's Hindu nationalist Bharatiya Janata Party won a surprise absolute majority in Uttar Pradesh in the north, which is home to 220 million people and seen as a key indicator of national politics.
Party leader Amit Shah called the win a "historic mandate" for the BJP and said it would also form governments in Uttarakhand, Goa and Manipur.
"These results will set Indian politics in a new direction," he said at a press conference at the party's New Delhi headquarters ahead of a formal election commission announcement of the results due later Saturday.
"The faith that people have placed in the BJP and in Narendra Modi will pay off."
The party won over 300 of the total 403 seats in Uttar Pradesh, way above the figure it needs to form a government on its own. It also won a majority in Uttarakhand, but the election commission website showed the opposition Congress Party led in Goa and Manipur with just a handful of seats still to be counted.
Shah said the result showed Modi, who personally led the campaign in the key battleground state of UP, was now "the most popular leader since independence".
The BJP had been expected to perform well in UP, but few experts had predicted the scale of the victory in elections viewed as a test of Modi's popularity after a controversial ban on high-value banknotes.
Experts said the results showed Modi had succeeded in tapping into popular anger over corruption with the move, which was aimed at tackling tax evasion but also led to widespread chaos in a country where most transactions are cash-based.
"People were more struck by the act itself than by its consequences," said Gilles Verniers, a UP expert at the Ashoka University.
"It was seen as a move that went beyond party and caste and affected everyone equally - notably the rich."
The results will also strengthen the BJP's hand in parliament's upper house, where the lack of a majority has hampered its reform agenda.
In a tweet, Modi said he was overjoyed by the "unprecedented support from all sections of society" and congratulated party workers.
Modi's dominance has been largely unchallenged since he won the first overall majority in three decades in the 2014 general election on a pledge to wipe out corruption and kickstart the economy.
He already looks well-placed for re-election in 2019 over the centre-left Congress Party, which the BJP ousted from power in 2014.
Deputy congress leader Rahul Gandhi congratulated the BJP on their win in a tweet and said his party would fight on.
With final results still awaited, Congress appeared to have taken just one state, Punjab, where it fended off a challenge from the fledgling Aam Aadmi Party.
In UP the party ran in an alliance with the locally ruling Samajwadi Party (SP), but were trailing in a distant second.
Low-caste leader Mayawati, whose Bahujan Samaj Party was in third place in UP, said the results were "shocking" and asked the election commission to investigate the possibility voting machines had been tampered with.
Celebrations broke out at the BJP's headquarters in state capital Lucknow where euphoric supporters danced to drum beats and handed out sweets. Many local voters said having the BJP in power both nationally and in the state assembly would be beneficial to UP.
"The state should now witness rapid development. Corruption and nepotism in governance would also come down," housewife Viti Kumar told AFP.
SP leader Akhilesh Yadav resigned as chief minister of the state and said he accepted the people's verdict "with humility".
The BJP was expected to announce his successor on Sunday.
The BJP fared poorly in the last UP state elections in 2012, winning only 47 out of 403 assembly seats, but it clinched 73 out of 80 parliamentary constituencies in 2014 with Modi standing in the holy city of Varanasi on the banks of the Ganges.
Its win in Uttar Pradesh will have significant implications for the make-up of the Rajya Sabha - the upper house of parliament. The Rajya Sabha is based on parties' strength in the state assemblies, with the biggest states supplying the largest number of MPs.