Voting began on Monday in the final round of Lok Sabha elections in Uttar Pradesh, West Bengal and Bihar.
In Uttar Pradesh, polling began today for the remaining 18 Lok Sabha seats, officials said.
The most keenly-watched contest is in Varanasi, where Bharatiya Janata Party's prime ministerial candidate Narendra Modi is locked in a battle against Aam Aadmi Party chief Arvind Kejriwal and Ajay Rai of the Congress.
Samajwadi Party chief Mulayam Singh Yadav is contesting from Azamgarh, while Quami Ekta Dal leader Mukhtar Ansari is in the fray from Ghosi.
A total of 328 candidates are in the fray. Over three crore are eligible to vote. Balloting is taking place at 31,483 polling stations where more than 146,000 personnel have been deployed.
In West Bengal, balloting is under way for the remaining 17 parliamentary seats of the state.
In Dum Dum, two former union ministers, Saugata Roy of the Trinamool and BJP's Tapan Sikdar, face Communist Party of India-Marxist's Asim Dasgupta, who was the state finance minister for 24 years.
Subhashini Ali of the CPI-M takes on Trinamool heavyweight and former railway minister Dinesh Trivedi in Barrackpore. Famous magician P.C. Sorcar Junior is fighting on a BJP ticket from Barasat. CPI-M's Sujon Chakraborty is pitted against Netaji Subhas Chandra Bose's grandnephew Sugata Bose (Trinamool) and painter Samir Aich (Congress) in Jadavpur.
A total of 188 candidates are in contention for the Lok Sabha seats. Besides, by-polls in two assembly constituencies are also taking place where nine candidates are contesting.
Balloting is taking place at 31,392 polling booths, where over 2.5 crore people are eligible to exercise their franchise.
Voting in Bihar began for six parliamentary seats in the last phase of general elections, officials said.
The constituencies where voting is taking place are Valmiki Nagar, West Champaran, East Champaran, Vaishali, Gopalganj and Siwan.
Among the prominent candidates are former union ministers Raghuvansh Prasad Singh and Raghunath Jha, filmmaker Prakash Jha, Hena Sahab, wife of jailed former MP Mohammad Shahabuddin, and Anu Shukla, wife of jailed former legislator Munna Shukla.
In West Champaran, Prakash Jha is pitted against incumbent MP Sanjay Jaiswal of the Bharatiya Janata Party and Raghunath Jha of the Rashtriya Janata Dal. A total of 90 candidates are in the electoral fray.
Polling is taking place in 8,582 polling stations. Over nine million people are eligible to vote.