In Boston, JetBlue was the fastest-growing carrier in 2008, adding an average of 190 passengers daily. In the current quarter, strong Florida traffic makes JetBlue Boston's No. 1 carrier. In Orlando, where it has added international flights to Bogota and San Jose, Costa Rica, JetBlue will be No. 2 this summer. At Fort Lauderdale-Hollywood International Airport, JetBlue will have seven contiguous gates this spring, up from four today, and it will add flights to Santo Domingo and Cancun in June. Of course, many airlines have struggled to build a franchise in Florida, where someone is always willing to charge a little bit less for a flight. In JetBlue's case, that someone is Spirit Airlines. Privately held Spirit is off the radar for many industry observers, but it is the largest carrier at Fort Lauderdale International Airport, carrying about 20% of airport passengers. In the Fort Lauderdale-La Guardia market, where Spirit has seven flights a day and JetBlue has five, Spirit cost per available seat mile is 20% lower because it packs in its passengers, says Spirit CEO Ben Baldanza. "They're a good airline, but they sell product, while we sell price," Baldanza says. "They can't make money at the fares we charge." Baldanza says South Florida to the Caribbean may also be a tough market for JetBlue, caught between price leader Spirit and well-established American ( AMR). And Orlando, he said, is a leisure market with limited traffic: "We've tried a number of things out of Orlando -- it doesn't work," he said. Overall, Baldanza said, JetBlue is a New York airline, hurt by the financial services meltdown and " playing the same game a lot of legacy airlines play, figuring out where its planes are losing money and how can they be redeployed to places where they will make money."