AK under pressure against maniac, 10/25 NL

[FoxwoodsFiend]

10/25 NL at the Borgata. Effective stacks are $3800. Villain is completely loony, talking to himself in a sing-song voice all the time, betting huge randomly, constantly reraising middle pocket pairs preflop, etc. Still, he does not seem indifferent to money.
I had played two noteworthy hands against him. One time I raised UTG and he reraised to 250 and I called w/AT. Flop came 888, I bet 500 and he raised to 1500, I folded and he showed 66.
Then, 2 hands before this one I picked up AA and raised to 100, he reraised to 400, I reraised to 1300 and he called. Flop came K82, he checked, I pushed all in for 2000 and he thought for 10 minutes before folding JJ.
Anyway, 2 hands later I pick up A [img]/images/graemlins/diamond.gif[/img] K [img]/images/graemlins/heart.gif[/img] UTG and raise to 75. 3 callers to villain who calls, and big blind calls.
Flop (460): K [img]/images/graemlins/club.gif[/img] 6 [img]/images/graemlins/diamond.gif[/img] 4 [img]/images/graemlins/diamond.gif[/img]
BB checks, I bet 300, folded to villain who raises to 900, BB folds.
What's my line?