Tamil Nadu Chief Minister J. Jayalalithaa was re-elected to a second term and the Bharatiya Janata Party (BJP) made political inroads into newer parts of the country with its first election victory in the north-east in Assam state.
Millions of Indians voted over seven weeks in Tamil Nadu, Kerala, West Bengal, Assam and in the union territory of Puducherry in a process Prime Minister Narendra Modi had called a "festival of democracy".
Ms Jayalalithaa, the 68-year-old leader of the All India Anna Dravida Munnetra Kazhagam (AIADMK), became the first leader in over three decades to win a second term in Tamil Nadu.
AIADMK won 123 seats and was leading in 11 seats at press-time, while rival Dravida Munnetra Kazhagam - which did better than in the 2011 elections - won 81 and was leading in eight seats. Results were declared for 232 assembly seats.
"I am overwhelmed by the resounding victory," Ms Jayalalithaa told the media.
In spite of rumoured poor health, she is seen to have scored big, particularly with women, who outnumbered male voters, with promises of welfare schemes and freebies, including a 50 per cent government subsidy on motorcycles for women
In the east, West Bengal Chief Minister Mamata Banerjee, 61, pulled off a massive win to return to power for a second term, defeating a Left-Congress alliance. She won 209 seats and was leading in two others. There are 294 assembly seats.
In India's federal structure, state elections have a direct bearing on national politics as they determine the composition of the Upper House of Parliament. The BJP, which has a majority in the Lower House, has been struggling to pass key legislation like the Goods and Services Tax Bill in the Upper House, where it is in the minority.
Though the BJP's win in Assam will not give it a much-wanted majority, it is seen as a boost for Mr Modi and a party laid low by last year's electoral defeats in Bihar and Delhi.
The BJP also for the first time won one seat in Kerala.
In Assam - which borders Bangladesh and Bhutan - the BJP stitched up an alliance with local parties and fielded local leader Sarbananda Sonowal as its chief ministerial candidate. It also gained from inducting local former Congress heavy-hitters into its ranks amid an aggressive campaign promising to stop illegal migration from Bangladesh, a highly emotive issue in the state.
Still the biggest electoral setback was for the Congress, which, apart from Assam, also lost in Kerala, where the ruling alliance it led lost to a Left-backed coalition. It did win in Puducherry. The Congress, which is in power in six states, is in serious trouble, said analysts.
"It is time for the Congress to do some serious introspection. It has been retreating from power in state after state. For the BJP, this is a huge boost for its effort for a pan-Indian identity," said Dr Sandeep Shastri, pro vice-chancellor of Jain University in Bangalore. "But the third big message from these elections is that... the real rivals (to Modi) will be state-based parties... not the Congress."