The Congress said on Friday that the opposition was committed to field "the most credible and winning face" in the presidential elections due in July.
Congress spokesperson Abhishek Manu Singhvi told reporters that the opposition would contest to win the election and every possible effort is underway "without fear, favour or restriction and ego" to select a credible face.
"All synergies of the wider opposition are being constructively pooled for that endeavour and result. We are fighting to win," he said.
Singhvi said many meetings had taken place and there will be more such meetings.
"A widest consultative process alone can generate that degree of consensus where everybody's private individual predilection and ego is submerged for the larger common good.
"The widest spectrum of the opposition is committed to ensuring the most credible and winning face in the presidential election to give a befitting reply and to fight to win the election against the NDA nominee," Singhvi said.
His remarks came even as the ruling National Democratic Alliance has not declared a candidate nor given any indications about the nominee.
President Pranab Mukherjee's term will come to end in July.
Congress sources admitted that the BJP-led NDA has an advantage in the electoral calculations for the presidential elections but insisted that a nominee with "high moral authority" can tip the scales.
They said that the presidential election is not fought on the basis of numbers alone and the candidate's name and personality matters and a candidate acceptable to large section can also get votes of fence-sitters.
The sources admitted that among the names being considered was that of former Governor Rajmohan Gandhi as he has an "all-India appeal".
Congress president Sonia Gandhi has taken the initiative to build consensus on on fielding a common opposition candidate in the presidential elections. She has already met several opposition leaders and is slated to meet West Bengal Chief Minister Mamata Banerjee next week.