Split Vote

A split vote is a strategy employed in Survivor by larger alliances in an attempt to avoid one of their own being voted out by the use of a Hidden Immunity Idol. The strategy involves the alliance casting an equal or near-equal number of votes on two different members of the opposing alliance, theoretically ensuring that one of them is voted out regardless of whom the idol is played on. In order for the split to work, the alliance must have a two-thirds majority.

In seasons with the "previous votes" tiebreaker, a similar strategy could have been used had any one alliance ever obtained a two-thirds majority, but the scenario never came into play.

The split vote was devised by Cao Boi Bui in the episode "Plan Voodoo", but the Aitutaki tribe opted to vote Cao Boi out rather than attempt a risky move that could have eliminated a strong physical competitor.

List of known split votes
The original intent of the split vote was for Tyson to vote for Russell to split the votes 3-3 between Russell and Parvati. However, Tyson voted for Parvati instead, ironically resulting in his own elimination.