Start a 3 player game, and after the game starts, add an audience member. This will make it easy to split votes and keep everything straight.
In round 1, draw a red LOSE for both characters with P1, and something neutral like a black line with P2 and P3. During the voting, vote against P1 with the player and the audience member. For the other matchup, split the votes. This will award:
In round 2, draw a green WIN for both characters with P1, and something neutral for P2 and P3. This time, put both votes toward the WIN character, and split the other votes. Do not sub out characters from round 1, just to keep things straight. Just keep putting all votes on P1 and splitting the other votes. The achievement will pop at the end of the game.