Most likely Jasper. He was cordial towards the pack in Eclipse, even teaching them his skills. Then next would be Emmett. I doubt Edward would have befriended Jacob and the pack if Bella didn't ask him to be nice to them.

Edward is prejudiced against them since he's doesn't like Jacobs feelings for Bella, and Emmett's always looking for a fight.
Jasper seems like the more calm, reasonable type.

I think Jasper would befriend for them better for the same reasons as Gred and Kate up here, and because they would be good on a team, so Jasper, being the intelligent fighter (unlike Emmett), would see this as a great idea, in case more people, newborns or Volturi or whoever, would decide to attack.