They’re running on empty. Some 2,000 passengers were stranded on Monday after Auckland Airport ran low on jet fuel, thanks to a burst pipeline. The airport’s only source of fuel was reportedly damaged months ago by exploratory digging and finally ruptured Thursday, cutting supply by 70 percent. Since the airport is a private company, the government says it’s not to blame — though critics argue that it’s responsible for securing infrastructure. With only days to go before New Zealand’s general election, this could suddenly take off as a decisive issue.