Call all-in pre flop with 77?

[keats]

Down to the last 2 in a home game. I am on the button with 77. Other player raised to t400, I make it t1200 to go and he goes all in? Now I think he probably has a good hand because this has been a suprisingly tight heads up play, and I havent seen him move in without an ACE so far. However I have him out chipped 2.5-1. I am used to playing ring games so short handed play isnt exactly my specialty so any thing you can offer me about how you came to the conclusion to call or not to call would be great.