There is no doubt lot of black money is involved in any election by any party - TMC and CPM may not be any exception. From the confidence of Gautam Dev, it's clear there is some essence in his complain. If there is any willingness of concerned officers, they can catch some big fish. But it looks like all these agencies (regulated by central govt.) may not do enough investigation. It is quite clear from the statement of EC - "It is not the duty of the EC to look into the source of the money. We will only monitor the expenditure part. We have sent the complaint also to the income tax department and they will see if there is any disparity between the income and expenditure."