Prime Minister John Key leaves on a three-nation trip to the Pacific tomorrow with an eye on the fallout from Labour's immigration policy among Pasifika voters.The five-day visit, which takes in Samoa's independence day celebrations on Monday and stops in Tonga and Niue, includes representatives of other political parties as well as the Government's new economic development ambassador to the region, Shane Jones.Key said the trip was a good opportunity to make announcements \reflective of the sort of aid and work we do in the Pacific\.He will also be seeking support for New Zealand's bid for a temporary seat on the United Nations Security Council.\I'd be extremely hopeful that in the case of Samoa