I'm going with the Bruins. If I had to "rank" my allegiances, I'd have the Sox over the Bruins, but I've seen two Sox titles, and none for the Bruins. In other words, they're due, and I'm pulling for them to get over the hump soon.
Also, playoff hockey is just an amazing sports experience, and to be able to witness a Stanley Cup finals game in Boston would be insane. It's been 20 years since the Bruins made it that far, to the point where the memory has faded.
After that, I'm pulling for the Sox, and actively rooting against the Pats (since I'm a Bears fan.

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