"If the vote share of both RJD and JD-U in the recent Parliamentary poll in the state is combined it will go up to 45 per cent which will be enough to defeat BJP," he said.
"We will sit together and talk about the feasibility of such an alliance. The parties connected with the 'Mandal' concept of social justice will have to unite in the present political scenario. There is a need for change and we have to think about it. We will have to take everybody along," he said.
"The Mandal Commission is a bomb which RJD workers should be ready to ignite," Prasad told the two-day 18th foundation day function of the RJD.
Politics in Bihar had taken a sharp turn in the '90s after implementation of Mandal commission report providing reservation for OBCs in government jobs. The mandal forces had swept aside Congress from power since then.
Janata Dal came to power under Lalu Prasad in 1989 and continued to rule the state till 2005 when Nitish Kumar another OBC leader, who was with Lalu Prasad initially but parted company in 1994 to float a new party, replaced it.
Prasad whose closeness with rival Nitish Kumar was visible in recent days said prospects of an alliance would be discussed with the former chief ministers in the days to come. The RJD and Congress recently voted for the Jitan Ram Manjhi government on the confidence motion on May 23.
RJD and Congress also bailed out an embattled JD-U in the bypoll for two Rajya Sabha seats last month.
Faced with large scale dissension, Nitish Kumar's party was faced with a major challenge to see its two candidates through in the RS bypoll.
The JD-U nominees triumphed in the RS by-election with the help of RJD, Congress, CPI and Independents.
Prasad attributed the party's poor performance in the LS polls to lethargic workers.
"Our workers did not work hard like those of rival parties," he said.
"The BJP and RSS workers went around on bicycles in villages and campaigned for their party, but our workers just moved around me. We need to think about this and change," Prasad said.
He also said that the BJP made good use of social media and electronic gadgets to attract the youth in the age group of 18 to 30 years and promised them better employment opportunities.
"They (the BJP) used laptops, mobile phones, social media to campaign and mislead the youth. They promised employment and the young boys and girls influenced their parents to vote for BJP," added Prasad.
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