"The results in Tamil Nadu and Puducherry were affected by the 2G scam and these states were lost to other parties," the editorial in the latest issue of `Congress Sandesh` said.
Congress was part of the DMK-led alliance in Tamil Nadu.
The issue has come at a time when DMK chief M Karunanidhi is holding an emergency meeting of the party`s high-level Action Committee.
The editorial also noted the Congress has fared well in the Assembly polls by retaining power in Assam, returning to power in Kerala besides trouncing the Left Front Government in West Bengal with its alliance partner Trinamool Congress.
It also says that "the investigating agencies are looking into many high profile cases of corruption that have attracted a great deal of public attention.
"The handling of these cases constitutes a litmus test and the agencies involved should act without fear or favour and bring to book all those who are guilty, irrespective of their position or status," it said.
The DMK meeting, the first after the party`s drubbing in the Assembly polls in which it finished a poor third, is being held in the wake of the Delhi High Court denying bail to DMK MP and Karunanidhi`s daughter, Kanimozhi, in the 2G case. She is currently in Tihar jail.
The DMK`s direction to all members of the Committee to "participate in the meeting without fail" has fuelled talk in Congress that an important decision is likely to be taken by the Dravidian party.