Soft punchers that were successful

[TigerFan]

Winky Wright

[Comegalletas]

Currently Cesar Rene Cuenca (light welter from Argentina) fits the bill. 37-0-0, all of 1 KO. I have seen him fight, a very awkward fighter. Low level of opposition (hardest was a disputed decision to Alex de Jesus), so his KO number is even more amazing.

I know, he is not still world-class, but I am sure he will contend for a world title down the road.