- 80% voting in 18 constituencies in West Bengal, 70% in 65 seats in Assam
- In West Bengal, TMC faces tough fight from Left-Congress combine
- In Assam, face-off between ruling Congress and the BJP-AGP-BPF alliance
Here is a 10-point cheat-sheet to this story:
While Assam has seen high voting in recent years, today's 80 per cent will be pegged by the BJP as a vote for change. The Congress' Tarun Gogoi has been Chief Minister for the last 15 years.
In West Bengal, the Election Commission said, the over 80 per cent turnout is four per cent less than 2011 in the constituencies that voted today. Chief Minister Mamata Banerjee is seeking a second term in West Bengal, where elections for 294 seats are being held in six phases.
The ruling Trinamool Congress expressed satisfaction over the turnout in the first phase of West Bengal assembly polls and said the record turnout proves the 'silent revolution' that Chief Minister Mamata Banerjee had ushered in through development.
Assam is voting in two phases, the second next Monday. 65 constituencies, mostly in Upper Assam which is a traditional Congress stronghold, voted today and are expected to play a key role in determining whether the BJP will be able to deny Tarun Gogoi a fourth term.
The Congress had swept the region in the 2011 assembly elections , but in the 2014 national elections the BJP won the most Lok Sabha seats in Upper Assam and hopes to convert that into assembly seats now.
While voting in Jorhat today, Tarun Gogoi said , "I don't think it is a tough battle. I will be the Chief Minister again." The veteran politician had turned Prime Minister Narendra Modi's comment on his age into what he has called a matter of "Assamese pride".
The BJP has partnered with regional parties the Asom Gana Parishad (AGP) and Bodoland People's Front (BPF) and has positioned union minister Sarbananda Sonowal as its candidate for chief minister.
In West Bengal Ms Banerjee takes on a Congress-Left alliance and the BJP, which has so far been a minor player, but hopes to make major gains this year.
Both Mamata Banerjee and the BJP have mocked the Congress and the Left for their alliance. The two parties are bitter rivals in Kerala, where assembly elections will be held next month.
Votes will be counted for Assam and West Bengal on May 19, along with Kerala, Tamil Nadu and Pondicherry.