The problem wih just calling is that you might lose your stack to K10 on a 610K, 2 suited flop. 2 pair crop up often in these bloated multiway pots, and its going to be tough to laydown TPTK given the action thus far. Plus, AK is so much better when you see 5 cards, and there is a nice amount of chips already in the center. Push and hope someone puts you on 7s, decides they have pot odds, and makes a heroic call with AQ.