Why is it so difficult for BJP to sack Yeddyurappa? That the man is corrupt is so obvious. The evidence is mounting. If he is not sacked immediately, then BJP will lose the position it has built in Karnataka. That Yeddyurappa has contributed to that should not be reason enough to stick to him now.
BJP can gain a lot by letting Yeddyurappa go and after 5-6 months call for a flash election with someone else - perhaps Ananthkumar - at the helm and may end up with a better majority that what it has currently.