I threw in offensive because I think Dame is better but if you consider the other 50% of the game, it's tough to see where Dame has so much of an offensive advantage to negate the defensive gap.
Lillard - 26.8 ppg, 4.5 rebs, 6.3 assts, 0.8 stls, 2.7 TOs. Shoots .455 FG%, .355 3Pt% and .893 from the FT line where he gets 7.7 FTA per game.
Butler - 25.5 ppg, 6.8 rebs, 4.5 assts, 1.7 stls, 2.1 TOs. Shoots .456 FG%, .336 3Pt% and .880 from the FT line where he gets 9.5 FTA per game.
Points are very similar, Butler gets significantly more rebounds, Dame significantly more assist. Butler doubles up on steals, they shoot almost identical numbers from the field, Dame is just a touch higher from '3' (I thought that would be bigger) and they are close at the line but Butler gets there about 20% more often.
So it is quite close offensively but when you consider the defensive impact, I think that is where Butler separates himself.