Prime Minister Narendra Modi’s Bharatiya Janata Party (BJP) is on course to win a landslide majority in India's richest state of Maharashtra, trends show.
The BJP and its allies are leading on close to 220 out of 288 seats, comfortably placed above the halfway mark needed to form a government.
Maharashtra, which has India's financial hub of Mumbai as its capital, is one of the most politically crucial states in the country.
The BJP, however, is staring at a defeat in the eastern Indian state of Jharkhand, where main opposition Congress and its allies are on course to win.
This was the first regional election in Maharashtra since the crucial parliamentary polls earlier this year, in which Modi returned for a historic third term but lost his majority, having to depend on regional allies to form a government.
Maharashtra was one of the states where the BJP suffered a setback and opposition parties won two-thirds of the parliamentary seats.
Modi's party currently runs the incumbent government in Maharashtra along with breakaway factions of two regional parties, the Shiv Sena and the National Congress Party (NCP).
Political analysts say the BJP's retention of the state will give a much-needed boost to the party, which also won regional elections in the northern state of Haryana last month.
"This result has taken us by surprise. We knew we would win but never expected such an overwhelming result," BJP spokesperson Pravin Darekar told reporters in Mumbai.
The outcome will also decide the fate of regional heavyweights, many of whom switched parties overnight in both states.
In Maharashtra, Modi led his party's campaign from the front, announcing several welfare schemes, many of which were aimed at farmers. The state is a major agricultural belt and producer of crops like onions, soybean and cotton.
The opposition also made similar promises, including waiver of farm loans and financial assistance for women and senior citizens.
Critics have pointed out that the competing poll promises would mean the new government would face a serious fiscal challenge in delivering them, or risk facing voters’ anger.
The state has undergone significant political turmoil in recent years. The BJP-led coalition stayed in power after some lawmakers from the Shiv Sena and the NCP broke away from their parties and joined the government.
Meanwhile, Jharkhand, where seven chief ministers have ruled since the state's formation in 2000, has also witnessed political upheaval in recent months after its chief minister Hemant Soren was arrested in February on corruption charges, which he denied.
After his release in June, Soren soon hit the road, trying to capitalise on sympathy votes.
While the BJP called Soren corrupt, he alleged that the the federal government was unfairly targeting a tribal chief minister.
Tribal communities make up nearly 9% of India’s population and remain one of the country’s most marginalised groups.
Like Maharashtra, Jharkhand also saw parties promising cash incentives, free power, jobs and health insurance.