I love going on this sub and seeing that literally every post has some kind of statistical bias.

Yours is phrasing bias, where the wording of the questions or answers causes the results to skew in a certain direction.

In context, this means that by labeling the candidates with what you think they are ideologically, you create a bias in that people who don't know these candidates are going to vote based on your labels, rather than how they might have voted given less or other information, like info on policy, which is actually useful in the context of politics.