SEATTLE -- There is a new battle in Seattle when it comes to air travel and you could be the one who benefits the next time you book a flight.
Sea-Tac International Airport is becoming more important than ever for airlines. Now Delta Air Lines is moving in on what has long been Alaska Airlines turf.
Aviation analyst Steve Danishek has been tracking Delta's Sea-Tac push. At the beginning of the year, Delta offered 38 daily flights from Sea-Tac.
By June, that nearly doubled to 79 flights. By next summer, Delta wants to have 100 flights -- and 150 or more by 2017 -- with a growing emphasis on international flights to places like Hong Kong, Shanghai, Seoul and Tokyo.
Delta plans to feed those flight with more domestic options to places like Los Angeles, Sand Diego, San Francisco and Phoenix.
"Seattle has a huge metropolitan market," Danishek said."A lot of international travel, so this is a natural place to put it to grow a new to grow a new international hub here."
But Alaska Airlines is not going to give up its Seattle air supremacy so easily.
"Alaska Airlines has been the dominant carrier here at Sea-Tac. Alaska and its sister airline horizon making up more than 50 percent of all flights in and out of this airport," Danishek said.
And Alaska is adding even more service -- now offering 537 daily flights to and from Seattle to 79 destinations.
This year Alaska added six new routes. Next spring its Sea-Tac traffic will grow by 11-percent.
"As Seattle's hometown airline, we offer service to 3 times more cities out of SeaTac than any other carrier," an Alaska Airlines spokesperson said.
And Alaska fought back when Delta became the official airline of the Seattle Seahawks, flying home the Super Bowl champions.
"So what did Alaska do?" Danishek said. "They came back and adopted Russell Wilson. Brilliant!"
More flights and more options has travelers at Sea-Tac hoping for cheaper flights.
But analysts say don't expect fares to hit rock bottom. With so much competition for Sea-Tac, other airlines -- like United, Virgin America, Southwest and Frontier -- may pull back and eliminate some flights.