With the Aug. 1 referendum just days away at this point, groups in support and against the plan for a new Nassau Coliseum are ramping up their efforts to swing the vote in their favor. Union officials, county officials and New York Islanders’ supporters gathered at the Nassau Coliseum Wednesday night for a rally to get out the vote in favor of the rebuilding plan. The main draw of the rally was Long Island native rockers Blue Oyster Cult performing in the outdoor plaza of the Coliseum, although Islanders’ owner Charles Wang, County Executive Ed Mangano and several others used the opportunity to speak to the crowd of roughly 2,000 people that had gathered for the free show. Meanwhile, the Association for a Better Long Island, one of the groups opposed to the Coliseum plan for financing the upfront cost of the project using taxpayer money, held a rally of its own Thursday morning outside the old County Courthouse building in Mineola, demanding that the Nassau Interim Finance Authority say it will block the project, regardless of the outcome of the Aug. 1 referendum. If the Aug. 1 referendum is approved by the voting public, the proposal would still have to be approved by NIFA, the county Legislature and the county comptroller’s office. If any of those entities were to vote against it, the plan would be effectively dead. Of the three, NIFA is considered the one most likely to squash the proposal. But Mangano and Wang are taking the plan one day at a time, focusing on the referendum vote for now. “We can’t worry about what’s next,” Wang said at a discussion Tuesday night. “Right now we’re focused on the Aug. 1 referendum. When that passes, we’ll worry about the next steps.”