At present it looks like the sportsmanship badge is only awarded once (at least I assume this because it doesn't explicitly say it's awarded multiple times on the badge page.) Would it make sense to change this so it's awarded multiple times, so it works for every 100 competing answers upvoted?
I doubt this feature would be abused since it involves essentially putting your answers at a disadvantage, and it'd still encourage people to keep on fairly upvoting competing answers even after they've already upvoted 100.