let them move it to some other city in India.
I don't think there is any other city in India that can host an ATP tournament. Anyway, ifeven there were, that would definitely not happen. If it stays, one of the reasons will be the backing it gets by the Tamil Nadu government. Nothing like that would be there in any other state in India. If the tournament moves out of Chennai, it will move out of India.
It seems that the Chennai Open is having a good year(2013 edition) in terms sponsorship. As expected, it seems that if Aircel continues its sponsorship there is no reason for the tournament to move out.