Christie has basically said he'll step back and let the voters vote on an amendment, so NJ will likely have it within the next few years.
I'll also go with 1 or 5. There's too many small states that aren't going to legalize it any time soon without court decision.
My guess is that New Jersey Democrats will reach an agreement after Christie's re-election (provided Dems lock down the State Senate and Assembly again) to put marriage on the ballot. There's been a lot of resistance from Dems on the grounds of principle, but since a statewide vote is a slam dunk, not a lot of people are hung up on that principle anymore.
Don't forget the New Jersey Supreme Court as a wildcard -- it's a very liberal institution that has been looking closely at whether or not civil unions are doing what the court required.
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