Former Lok Sabha Speaker Meira Kumar and Prakash Ambedkar, grandson of BR Ambedkar, the architect of India’s Constitution, have emerged as frontrunners of the Opposition camp to take on the NDA’s presidential nominee Ram Nath Kovind.The Opposition parties will be meeting at 4pm on Thursday to finalise their candidate for the presidential poll that will take place on July 17.Like Kovind, both Meira Kumar and Prakash Ambedkar belong to the Scheduled Castes. Meira Kumar is the daughter of Dalit stalwart and former deputy prime minister late Jagjivan Ram. The 71-year-old Kovind’s candidature was seen as a masterstroke by Prime Minister Narendra Modi as it created a divide in the opposition that was trying to put up a consensus candidate. Many in the camp were averse to the idea of opposing a Dalit and some, such as the BJD, TRS and YSR Congress, had already announced their support. Both factions of the AIADMK -- E Palanswami and O Panneerselvam -- too have said they will back Kovind.On Wednesday, Nitish Kumar’s JD(U), widely expected to join the opposition meeting today, announced they would support Kovind’s candidature. His coalition partner in Bihar, Lalu Prasad’s RJD, remains with the Congress-led opposition. Though Nitish has remained tight-lipped, the announcement to support Kovind came from his party colleague KC Tyagi, a former Rajya Sabha member.But now the candidature of Meira Kumar, a Dalit leader who hails from Bihar, could put Nitish in a spot. He will have to find a justification to back Kovind, who is from Uttar Pradesh , and not the former Lok Sabha Speaker.The Left parties were said to be in favour of Prakash Ambedkar’s candidature, although Left sources said they were not opposed to Meira Kumar either.Some opposition leaders, including CPI(M) general secretary Sitaram Yechury and Congress veteran Ahmed Patel, on Thursday met at NCP leader Sharad Pawar’s residence. After the meeting, Yechury said, “Our choice is either Gopal Krishna Gandhi or Prakash Ambedkar.” Former home minister Sushil Kumar Shinde and Balchand Mungekar were said to be the other opposition options. But the Shiv Sena’s support to Kovind may have ruled out Shinde, a leader from Maharashtra. The Sena earlier had ditched the BJP to back Pratibha Patil for Maratha pride.Kovind was expected to have a smooth ride and the only debate now is about the former Bihar governor’s victory margin.