I agree with others, that I dont want to just call here and allow CO to dubble flat, so that I have to play an awkward side pot against him out of position. If we jam, he is mainly going to fold, because usually he has some kind of marginal hand, where he just want to use his position to try to outplay us postflop.
So we can basically consider this an all-in for 12BB, and since this is only 25% of our chips, we dont need to give great consideration to ICM. Which mean we can just do the math and then pull out Equilap (free software) and give him some ranges to see, where the break-even point is for us to call this off.
We are calling 2.981 to win 8.838, which mean, we need at least 33,7% equity. This is not a lot, but if his jamming range is 88+, AJ+, then we only have 33,2%. And I think, this is fairly realistic, because he is facing an UTG open, and he should know, his fold equity is limited with just 12BB. Some might jam even tighter like AQ+, 99+, and then we only have 32,1%.
For us to make money by calling here, we need him to have hands, we are ahead of. If we widen his range to A9s+, A2s-A5s, QJs+, 66+, now we have 42%, and this is definitely enough to make me want to call this. But this is a 2$ tournament, and how many players are actually jamming all those hands against an UTG open? If he just lost a big pot and might be on tilt, I would lean towards a call. But if he has been playing tight and now suddenly wake up with this jam, I would fold.
We also need to remember, that CO folding is the ideal scenario. There will be some percentage of the time, where he call our jam, either because he was trapping with KK, or because he cant lay down a hand like 88 or AJ. This cuts into our profit, so we want to make some actual profit, when CO fold. We dont want this to be super marginal to break even.
Results
Checked the results now. Him showing ATo mean, his range was wide enough for us to give him action, because if he can have this, he can also have some suited aces or KQs type hands, that we beat. And of course always nice to bink a huge suck-out by beating the same hand with a flush