That's what I would describe as someone not considering a hypothesis, and then later starting considering it. That is not what I would describe as someone subconsciously considering a hypothesis the entire time, at least without further justification.

Remember that not considering a hypothesis is not the same as saying the hypothesis has a low probability. Saying the hypothesis has a low probability is considering it and then discarding it. I think we're talking about two different things.

I can't think of any non-politically-charged examples at the moment, but consider for example the sort of confusion that leads someone to ask "So are you Blue or Green?" of someone who's just finished explaining that they're Red.

That reminds me of what Scott Adam's called The Two-Bucket Mind.