ZURICH, Sept 27 (Reuters) - Swiss voters backed the government's plan to spend up to 6 billion Swiss francs ($6.46 billion) on new fighter jets in a surprisingly close referendum that was won with a 50.1% majority, Swiss television reported on Sunday.

Approving funding in the binding referendum would let the government decide next year among the Eurofighter from Airbus , the Rafale from France's Dassault, Boeing's F/A-18 Super Hornet, or the Lockheed Martin F35-A Lightning II.

The aircraft would replace Switzerland's aging fleet of 30 F/A-18 Hornets, which will go out of service in 2030. ($1 = 0.9284 Swiss francs) (Reporting by Michael Shields; Editing by Alison Williams)