The Congress is likely to approach the Election Commission to protest against the "misuse of government machinery" in the Rajya Sabha elections for two seats in Haryana on Saturday which led to independent candidate RK Anand, backed by it, losing the poll.
Party general secretary BK Hariprasad is consulting legal experts on the issue, Congress sources said.
Former CM BS Hooda said "If all 12 votes were cast using same pen, it indicates towards a conspiracy by BJP & election machinery."
"Matter should be probed, everything will come out if election petition is filed,"he added.
The party is alleging that there was deliberate fraud in the election by switching the pen meant for marking the votes so as to make the Congress votes invalid.
The votes of 14 Congress MLAs were declared invalid leading to the loss of Anand who was otherwise expected to win.
Hariprasad had on Saturday said that prima facie he saw a conspiracy from the government's side and said the party will find out the truth. "We will fight it politically and legally," he had said.
The defeat of Anand came as a bolt from the blue for the Congress and its high command, which was confident that its strategy to trounce the Bharatiya Janata Party (BJP)-backed media baron and independent candidate Subhash Chandra would succeed.
On Friday, the Congress Legislature Party at its meeting had authorised party chief Sonia Gandhi to decide on who to vote for and she had directed voting in favour of Anand.
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