AJo: Folding good money after bad?

[SamIAm]

MP3 is a LP-P moron. SB is LA-A and MP2 is a smart sLA-A.
Party Poker 2/4 Hold'em (9 handed) converter

Preflop: SamIAm is UTG+1 with Jh, As.
1 fold, SamIAm raises, 1 fold, MP2 3-bets, MP3 calls, 2 folds, SB calls, 1 fold, SamIAm calls.

Flop: (13 SB) Th, 2s, Qc (4 players)
SB bets, SamIAm raises, MP2 3-bets, MP3 calls $4.25 (All-In), SB caps, SamIAm calls, MP2 calls.

Turn: (13.56 BB) 3c (4 players, 1 all-in)
SB bets, SamIAm folds, ...

The pot's big and I have an overcard and a gutshot straight. That means I'm not gonna fold, so I should raise to try to clear my ace draw. I think it's a good raise against a maniac.
I don't like being 3-bet, and the cap should have terrified me. I think I should have folded to the cap, because suddenly my ace outs seem less likely and the king outs aren't strong enough.

The problem was, I realized this on the turn, and folded there. I now wonder if I should have called THIS bet, just on the K draw. Now raising doesn't clear any outs I value, so maybe call? I don't want to see another raise, and definitely not a 3-bet, but is the draw worth it?
-Sam