But his government's inability to create a million jobs every month, and ease farmers' distress over low product prices, has taken the shine off what is still the world's fastest growing major economy. From sugar farmers in northern Uttar Pradesh going unpaid for produce, to small businesses in the south shut because they are unable to meet the requirements of a new, unifying national tax, discontent has brewed for months.
"The election has become a lot closer than we think, sitting in Delhi," said Nilanjan Mukhopadhyay, author of a Modi biography and books on Hindu nationalist groups. "There is anger and disillusionment in the countryside." In December, alarm bells rang for Modi's Hindu nationalists after it lost three key states to the main opposition Congress and its allies, led by Rahul Gandhi.
But a surge in tension with traditional foe Pakistan in February has pushed Modi ahead, as he projects himself as a defender of national security and paints his rivals as weak-kneed, sometimes even questioning their patriotism. "People were very unhappy, angry that Modi makes tall promises and doesn't deliver," said Shiv Chandra Rai, an Uber driver in the commercial capital of Mumbai.
"Everyone said there are no jobs, everywhere farmers are struggling. But on this issue of Pakistan we are confused now. Some people feel we have to vote for Modi on this issue, it is a national problem." A regional leader of a Hindu group linked to the BJP and his bodyguard were killed by gunmen who burst into a hospital in occupied Jammu and Kashmir on Tuesday, police said, underscoring the BJP's concern over security in the region.
The BJP was also targeted in Chhattisgarh, when a bomb set off by left-wing militants killed a regional party legislator and four people with him. The Congress, led by Gandhi, and his charismatic sister Priyanka Gandhi Vadra, who took up a party post in January, wants to steer the campaign back to Modi's broken promises on the economy.
Gandhi has pledged a monthly payment of 6,000 rupees for the poorest families, about 250 million of a population of 1.3 billion, in a bid to stamp out poverty. "Congress is trying to pitch in the election with regard to farm distress, rural crisis, unemployment," said Sanjay Kumar of new Delhi think tank the Centre for the Study of Developing Societies.
About 900 million people are eligible to vote in the election, spread over seven phases into next month so that security forces can ensure a free and fair ballot at about a million polling stations. Results will follow vote-counting on May 23.
Congress has said Modi's party presents a threat to every opposition group by pursuing its vision of a Hindu-first India, stoking fear among the Muslim minority.