Delta Air Lines amps up battle vs Alaska Airlines, in Hawaii and Alaska

Delta Air Lines Inc. (NYSE: DAL) is upping its game against Alaska Airlines by adding new flights in two of Alaska Air's key markets: one warm, one cold. Atlanta-based Delta Air Lines, which has been muscling into Alaska territory, on Monday announced new flights from Seattle-Tacoma International Airport into Hawaii and Alaska. On the warm side, Delta in December will start a daily nonstop flight form Seattle to Hawaii's Big Island, giving it daily non-stops to three Hawaiian Islands: Oahu, Maui…