Spirit Airlines was the budget-friendly carrier America loved to hate. But now that it’s out of business, a viral crowdfunding campaign is attempting to resurrect the bankrupt airline. Once Hunter Peterson heard Spirit would close on May 2 — after attempts to merge with other airlines or get a lifeline from the federal government — the 22-year-old voice actor and content creator posted on social media that day with an idea to revive the airline. If a fifth of Americans each pitched in $45, (the equivalent of a cheap Spirit flight) “we could buy Spirit Airlines,” he said. His initial pitch was to run the airline like the Green Bay Packers, the only publicly owned team in the NFL. It has more than 5 million shares split among more than 530,000 owners. His joke, however, became a call to action. Peterson is not taking actual cash, but he has rallied $337 million in pledges from more than 370,000 verified people, his website says.…