By DAVID KOENIG
AP Airlines Writer
JetBlue is trying to improve its chances of buying Spirit Airlines over government objections. On Thursday, JetBlue announced it had agreed to sell Spirit’s holdings at New York’s LaGuardia Airport to Frontier Airlines. The sale, however, is conditioned on JetBlue being able to complete its proposed $3.8 billion purchase of Spirit. The Justice Department and several states are suing to prevent JetBlue from buying Spirit, arguing that it would reduce competition and drive up fares. JetBlue hopes it can undercut the government’s argument by selling some of Spirit’s assets to Frontier, another low-fare airline.