If it was a head-to-head eviction with only 2 housemates up, whoever wins the save and replace task (providing it continues) could practically decide if they want the other nominee out by putting a housemate against them who they know would be popular outside and wouldnt go (Steve being the biggest example, Josie and Mario too - none that would get up by nominations itself for a while Id guess).
Would any of them play this dirty tactic, or would they fear their popularity within the house would decline?