[adanthar]

It depends on the exact card because the donk is also still technically in the hand, so (for example) if a spade hits and they check to me, I have to push. Actually, if he checks any turn, I may as well push now because I'm not getting anything else out of him at this point unless he hits.

If he pushed on a spade, I'd assume an As semibluff and call.

(BTW, results: <font color="white"> I hit the Qs on the turn, he bet 300, the donk folded, I pushed, he thought, evidently felt pot committed at over 4:1 and called with AK, no spade. </font> )