Kolkata: People lined up in large numbers outside the polling booths, as voting began at 7 am for the third phase of Bengal assembly election involving 62 seats spread over four districts on Thursday. Twenty two constituencies in Murshidabad, 17 in Nadia and 16 in Burdwan districts as also seven in north Kolkata are up for grabs. Thursday marks the second and final round of voting in Burdwan, where nine constituencies went to the hustings on April 11. Over 1.37 crore (1,37,42,000) voters are eligible to choose their legislators across 16,461 polling stations, including 10 auxiliary booths, from a field of 418 candidates -- 34 of them female. In the assembly polls in the 62 constituencies five years back, then allies Trinamool and Congress had captured 45 seats, with the Trinamool taking 29 and the Congress 16. Among the Left Front partners, the CPI-M had won 14, and the Revolutionary Socialist Party, Samajwadi Party and All India Forward Bloc one each. The ruling Trinamool, and the BJP are contesting in all the seats in this phase. The Left-Front Congress alliance is also in fray for all the seats. But the Congress nominees are also clashing with those from the Left Front in 11 seats a" 10 in Murshidabad and one in Nadia. In this phase, Ranaghat South in Nadia is the largest constituency electorate-wise, and Ausgram in Burdwan district the biggest in terms of area. Shyampukar constituency in Kolkata (North) has the least number of electors. Among the major candidates in this phase are state ministers and Trinamool contestants Rabiranjan Chattopadhyay, Sashi Panja, Sadhan Pandey, Subrata Saha, former state minister and CPI-M candidates Anisur Rahaman and Debesh Das, Congress legislature party leader Md. Sohrab and former state party president Somendranath Mitra and Ritesh Tiwari from the BJP. Of the 418 candidates in the fray, 61 are crorepatis, 80 have criminal cases against them, with 65 of them declaring serious criminal offences like murder and rape against their name. So far, voters in 105 of the total 294 constituencies have exercised their right to franchise on three dates -- April 4, 11 and 17 -- in the first two phases. West Bengal is having a staggered six-phase election. Polling for the remaining phases will be held on April 25, 30 and May 5.