LM have the F-35, Northrop the bomber and Boeing the tanker...............
I'd like to point out that the KC-46 is based on a fairly old airliner. Building KC-46s does not preserve an industrial base capable of designing and building tactical aircraft, especially agile fighter types. So if that is a consideration in the T-X competition (and it may or may not be a consideration), then Boeing's tanker does not enter into the equation.