[Mr.Poker]

This is a really good question.

My first thoughts is that there is an $11,000 bubble situation and the second is that the BB is a big stack who can easily afford to call an all in.

Im gona take the second question first and say that in terms of risk/reward and various ICM calculations, without actually doing them, I would estimate that the player on the button can only call correctly if he has AA.

However, pushing ranges can be wider than this. We know CO should not call us with anything less than AA (although I dont know how many players lay down KK), which means AQ is easily enough to push into his calling range.

The SB is a good tourney pro and probably knows that while you can push a wider range of hands than call, the big stack in the BB will likely reduce your pushing range significantly for fear of being called and busting out, and therefore, there calling range will be fairly tight. Considering this is for around half her stack as well, this reduces her calling range too.

The BB is where it is really interesting and difficult to answer this question confidently. The BB has a massive stack compared to Hero and can easily afford to call a push from Hero. The BB will know that Hero knows this, and therefore pushing onto his BB will show significant strength. However, unless you are only pushing a high pair, the BB can call with quite a wide range getting decent odds.

The problem is though, Im sure good tourney pros like to keep the bubble going as long as possible so it allows them to steal and resteal very aggressively and not get played back at nearly as much, which means he/she might fold more than we expect them to.

Mathematically im not certain what pushing ranges are correct here as it depends massively on the BB's calling range.

I would expect AQ is be right on the border but this is certainly a tough decision in any case.