A late evening announcement by Biju Janata Dal's Naveen Patnaik has given the ruling BJP-led national coalition's candidate a clear edge in the Rajya Sabha deputy chairman's election to be held on Thursday morning. Mr Patnaik's promise of support to Harivansh Narayan Singh, a first-time lawmaker from Nitish Kumar's Janata Dal United, places the NDA in a comfortable position vis--vis Congress lawmaker BK Hariprasad, the candidate supported by opposition parties in the 244-member house. Prime Minister Narendra Modi and BJP chief Amit Shah have worked the phones over the last few days to reach out to allies and friendly parties outside the alliance to ensure a win. It could be the NDA's first in the Rajya Sabha where it has been dependent on the opposition Congress to pass legislations.