You are totally wrong. Congress was the party that brought in and nurtured corruption (dont forget the Licence raj) and having been in power for most part, they have mastered the art of corruption. Besides, what do you say about some of the other parties on whose support the UPA exists. Are they also clean and if they are not, is not the Congress hypocratic in taking their support for their own survival?
In any case, besides the corruption, there is also the corruption of ideas, circumventing of systems, and methods employed for winning elections. These are equally (if not more) dangerous when the intention is electoral victory. These have a lasting impact on the country and will be almost impossible to be reversed. The Congress are past masters in the art of this.
The whole political system in India needs a major overhaul and unfortunately only the people in power could take steps for the overhaul and as we all know, they surely will not!!!!!!