OLIVIA PEDERSEN thought the Nissan Leaf parked outside her favourite lunch spot near Emory University, must be hers. But she could not open the door. Nor could she open the door of the identical Leaf behind it. Cautiously, she tried the third Leaf in line and happily drove away. More than 14,000 electric vehicles are now registered in Georgia; California is the only state with more. But the juicy state incentives for buying them are coming under attack.

Residents can claim an income-tax credit for 20% of the cost of leasing or purchasing an electric vehicle, up to $5,000. Combined with a possible federal tax incentive worth $7,500, savvy Georgians are driving all the way to the bank in nearly-free electric cars. Nissan sells more of its Leaf models in Atlanta than in any other city, according to Don Francis from Clean Cities-Georgia, which promotes the use of cars like these.

Such trends motivated Chuck Martin, a representative in Georgia’s House, to sponsor a bill to end state incentives for electric vehicles. He argues that the income-tax credit costs too much—about $13.6m in 2013—and that only urban types benefit from these sorts of cars. Mr Martin’s bill was voted down in committee in February, but seems to be still breathing. Another House bill, mostly to finance transport projects, would reduce the credits; it is now before the Senate.

Fans of electric vehicles say Georgia now leads the country in clean transport. Local power companies have helped by offering off-peak prices of 1.3 cents per kilowatt hour for charging the cars at night. And the sales tax levied on this power stays in the state, whereas cash spent on petrol largely goes elsewhere, says Jeff Cohen, founder of the Atlanta Electric Vehicle Development Coalition.

Cutting the credits altogether might also harm Georgia in other ways. A study by Keybridge Public Policy Economics, a consultancy, says the state could lose $252m by 2030 if they disappear and people buy gas-guzzlers instead. That is because drivers will spend $714m on petrol to get around (in contrast with the $261m they would have paid in electricity bills), and will no longer fritter away their savings from the federal electric-vehicle tax credit in Georgia’s shops. But the state’s incentives may be safe in the legislature after all; the president of the Senate drives an electric car himself.