Prime Minister Narendra Modi's party won a landslide victory in India's most important battleground state on Saturday, in a personal triumph that will strengthen his claim to a second term as national leader.
Wresting control of Uttar Pradesh is a ringing endorsement of Modi's stewardship of Asia's third-largest economy after his high-risk decision last November to scrap high-value banknotes worth 86 percent of the cash in circulation.
The Election Commission of India said Modi's Bharatiya Janata Party (BJP) had won a clear majority, according to partial results. The BJP was on course to win 309 of 403 seats in the state assembly, the biggest majority for any party in the state since 1980.
Almost four in ten voters backed Modi's party, the election commission said as it tallied the last votes, close to the party's vote share in Uttar Pradesh in the 2014 national election when it won the biggest national majority in three decades.
"I give my heartfelt thanks to the people of Uttar Pradesh. This is a historic victory for the BJP; a victory for development and good governance," Modi told his 28 million followers on Twitter.
Investors hope victory will embolden Modi to embark on more reforms, including the launch of a national sales tax, to boost economic growth.
"The outcome of this election will enable Modi to sharpen his winning anti-corruption and improved governance policies as he begins to position himself for the 2019 general election," wrote analysts Shailesh Kumar and Sasha Riser-Kositsky of macro advisory firm Eurasia Group.
Modi threw himself into the Uttar Pradesh campaign after his party got off to a slow start, addressing dozens of rallies and turning the contest into a test of his personal popularity and his radical move to abolish big banknotes to rein in corruption.
Celebrations erupted outside BJP offices in state capital Lucknow and Delhi, with party workers dancing and splashing each other with paint in keeping with the Holi festival of colors that Hindus are celebrating this weekend.
Modi's campaign manager, Amit Shah, credited the BJP victory to a corruption free and pro-poor administration. The BJP will discuss who will become the next chief minister of Uttar Pradesh on Sunday evening, Shah told reporters.
Results for four other state elections put the BJP ahead in the Himalayan state of Uttarakhand but losing control of the coastal state of Goa. In the northeastern state of Manipur, the BJP trailed the Congress party.
Congress won in Punjab state, offering at least some consolation after Rahul Gandhi, heir apparent to the party leadership, failed again to make an impact.
In Uttar Pradesh, a largely poor and agricultural state of 220 million people, Modi pitched himself as a man on the side of the poor prepared to hit the corrupt rich hard with his demonetisation drive.
The scale of the victory suggests Modi's appeal cut across caste and community in a state where most people traditionally vote along religious and social lines.
Critics accuse his party of stirring communal tensions to shore up votes among its core Hindu base, particularly after its campaign got off to a slow start.
None of the BJP's opponents, including the ruling Samajwadi Party, managed a vote share above 23 percent, official returns showed.
"The Samajwadi Party wholeheartedly accepts the verdict of the people of Uttar Pradesh," spokesman Ghanshyam Tiwari said, conceding defeat. Chief Minister Akhilesh Yadav was expected to resign later on Saturday.
The election decimates the field of credible opponents who could halt Modi's march to a second term at the 2019 general election.
Victory in Uttar Pradesh will also make it easier to overcome resistance to the BJP's legislative agenda in the upper house of parliament, where the ruling party is in the minority.
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