It appears he listened to his GOP handlers about as much as he’s listened to his constituents. Thankfully, his sheer arrogance has worked in our favor for once! :)
I think Lugar signed his death warrant when asked about his upcoming primary fight responded by saying, “do they know who I am?” It spoke volumes and the people of Indiana listened. Add that to the residency issue and he was toast. All Mourdock had to do was show he was a reasonable alternative which as a two time State Treasurer was pretty easy.