The victory for JetBlue comes after Spirit canceled its $2.7 billion sale to Frontier Airlines, but the potential takeover is expected to kick off a fight with antitrust regulators.

Shares of Spirit Airlines rose nearly 4% in early trading Thursday, while shares of JetBlue fell 3%, but shares of Frontier soared more than 10% as investors cheered the end of a takeover saga that began in April.

JetBlue and Frontier were locked in a bidding war to create a combined airline that would better compete with legacy carriers at a time when the industry faces a labor crunch and high jet fuel costs.

In February, Spirit had agreed to an offer from Frontier before JetBlue jumped into the fray with a higher offer in April. Despite JetBlue's better terms, Spirit had pushed for a merger with Frontier, citing antitrust concerns with a potential JetBlue tie-up.

But it could not muster investor support for the deal and was forced to delay a shareholder vote on the proposed acquisition four times.

Reuters had reported that Spirit shareholders were expected to vote against a merger with Frontier at the latest meeting which was set for Thursday.