I once worked at a place where the employees had petitioned for a union. After an election was scheduled, the management arranged for another union to also be in the running.

Since it was not a run-off situation, the second union was a very effective 'spoiler' candidate (they must have been aware of that fact; I have always thought that if they actually cared about helping workers, they would have backed off); the number of votes for the two unions combined was greater than the number against having a union -- but that number was greater than the number of votes for either union alone...

Divide and conquer. [sigh]