New Delhi: Counting of votes for the Lok Sabha elections, in which over 8,000 candidates were in the fray for 542 seats, will begin at 8.00 am Thursday and results are expected only by late evening due to tallying of voter verified paper audit trail (VVPAT) slips with EVM count for the first time.

An estimated 67.11 per cent of the 90.99 crore electors had cast their vote in the seven phase elections. This is the highest ever-voter turnout in Indian parliamentarian elections.

Most of the exit polls have predicted that the Bhartiya Janata Party (BJP)-led National Democratic Alliance (NDA) is on course to retain power for a second term, riding on Prime Minister Narendra Modi's charisma like the way he swept to power in 2014. However, the opposition parties have trashed results of the exit polls, claiming that the BJP will suffer severe drubbing due to rising unemployment, farm distress and slowdown in the economy.

In the 2014 elections, the BJP won 282 seats while the Congress had suffered a severe drubbing getting an all-time low of 44 seats as against 206 it won in 2009.

This is for the first time in a Lok Sabha election that results of voting machines will be matched with slips generated by paper trail machines. The exercise will take place in five polling stations per assembly segment which effectively means that out of nearly 10.3 lakh polling stations, the EVM-VVPAT matching will take place in 20,600 such stations.

The Election Commission is yet to provide the number of counting centres being set up for Thursday, saying the data is not centrally available.

As per procedure, postal ballots would be the first to be counted. Service voters stood at 18 lakh. These include personnel of the armed forces, central police force personnel and state police personnel who are posted outside their constituencies.

Diplomats and support staff posted in Indian embassies abroad are also counted as service voters. Out of 18 lakh registered voters, 16.49 lakh have sent their postal ballots to their respective returning officers as on May 17.

The exercise of counting postal ballots manually will itself take a couple of hours at least, an EC official said.

The paper trail machines slips will be counted in the end. As per the procedure, first the slips will be counted and the EVM displays would be switched on later to match the results. In case of a mismatch, the results based in paper slip count will be considered as final.

The entire exercise of EVM-Paper trail machine matching will take an additional four to five hours.

Out of the 543 Lok Sabha seats, elections were held in 542 constituencies as the EC had cancelled polls to the Vellore constituency on the grounds of excessive use of money power.

The poll panel is yet to announce a fresh date for elections in Vellore. Prime Minister Narendra Modi, several union ministers, Congress President Rahul Gandhi, UPA chairperson Sonia Gandhi and SP chief Akhilesh Yadav are among key leaders who contested the polls.