Drivers depend on gas tax revenue almost as much as they depend on gas.

The folks at Jabberwonk have put together a simple gas tax "holiday" calculator. Enter your car’s fuel efficiency and the miles you expect to drive, and the calculator spits out how much you would save this summer if the gas tax were suspended.

The formula assumes that the full 18.4 cents per gallon will be passed on to the consumer, an outcome most economists view as extremely unlikely. Even so, it’s difficult to come up with a scenario in which someone would save more than $100. But if you own a 16 mpg SUV and commute 50 miles each way, and drive 800 miles (roundtrip) for your vacation, that would do it. More likely, typical savings would work out to about $18 (and for many readers of this blog, probably zero).

Meanwhile, not content to let the gas tax holiday remain a pocketbook pander for the campaign trail, Hillary Clinton says she’s going to put the question to Congress. Is it savvy politics to keep this idea in the news cycle — running contrary to the experts’ consensus — or will voters sniff out a gimmick?