How about that it's significantly more expensive on average to execute a prisoner (due to the extensive appeal processes) than to imprison him for life? I would assume that should be a very compelling argument in favour of abolishing the death penalty for somebody who is "right of center".
I can understand why you would say that based on all of the stereotypes floating around, but honestly I've never seen this argument move the needle for anyone.
For some they just say 'I'll do it for a dollar' and disengage. Realistically the cost of incarceration isn't what's driving their argument for the death penalty, it's just a talking point.
For me, it's just the price of due process.
Maybe to save a few keystrokes, I think we are too flippant about the death penalty today but I think its an essential part of a justice system.