"Aaj ka din Congress aur SP ke rishton ki kurbani ka din hai (Today is the day for sacrifice of ties between Congress and SP)," party leader Amar Singh said at an election rally after Dimple filed her nomination papers.
Congress has fielded SP rebel Raj Babbar from the seat where byelection was necessitated after SP chief's son Akhilesh Yadav decided to vacate the seat and represent Kannauj in the Lok Sabha.
Singh attacked Congress for fielding somebody against the family member of the SP supremo who had saved the government on the floor of Lok Sabha during the trust vote last year on the nuclear deal issue.
He also hit out at Babbar for contesting against Dimple, saying that thrice the SP chief had sent him to parliament. "Perhaps, it is his lust for power which has made Babbar a traitor," Singh alleged.
On allegations that fielding of Dimple reflected nepotism in Samajwadi Party, Singh shot back how it was wrong if in the case of leaders of other parties it was right.