"This drive is a demonstration of the freedom the Volt will provide customers -- freedom to drive where you want, when you want," said Tony DiSalle, director of product marketing for Chevrolet Volt.

As much as we’re annoyed by automakers tooting their own horn -- and Chevy will apparently lean on the Volt’s all the way from Texas to Manhattan -- DiSalle has a point.

The Volt, of course, is a plug-in hybrid. It can travel roughly 40 miles on electricity alone, compared with the roughly 100-mile range of the all-electric Nissan Leaf. But the Volt’s trump card, cheekily demonstrated by this typical, Fourth of July interstate dash, is its range-extending gasoline engine, which kicks in to generate electricity when its lithium-ion battery runs low. Nissan Leaf buyers will likely never drive from sea to shining sea, or even much beyond their own ZIP code, unless they can string together endless, multihour charging stops. In contrast, the Volt can drive on electricity alone during weekly commuting runs, matching the Leaf by using not a drop of gasoline and producing zero tailpipe emissions. But the Volt can also make the holiday drive to grandma’s (with a 340-mile total driving range), quickly refuel at any gas station, while still delivering roughly 50 mpg in its gas-burning mode.

Nick Richards, a Chevy spokesman who saw the Volt off from Nashville, Tenn., said that the Volt "is a vehicle that can be your only vehicle. If you want it to be an electric commuter car, it can be. But it can also cover long distances."

Rubbing it in, Richards cited AAA, which calculated that about 34.9 million travelers will crisscross America over the holiday weekend. Most will drive their cars at least 50 miles from home, a distance beyond which most EVs would fear to tread, unless there was an charging oasis along the route.

I've argued that the Volt (if it works as advertised, and after initial sales euphoria for both cars dies down) is likely to trounce the Nissan in the marketplace, even if its roughly $35,000 price (after a generous $7,500 tax credit from the feds) may be about $5,000 more than the Nissan’s. Too many EV proponents, who insist they'd buy an EV tomorrow, are notorious for talking a big game, but not putting their money where their mouth is. Aside from true EV believers, most Americans, I’m convinced, are not ready to spend $30,000 on a car that’s largely tethered to their home charger, able to drive only 50 or 60 miles -- and that's best-case, with range dramatically reduced in high-speed driving or freezing weather -- before being forced to turn around and head back for a recharge.

EV backers brush away those arguments by talking about how easy it would be to wire up the highways and parking lots of America with charging stations, and that’s true. But closing your eyes and imagining the future, while a valuable exercise in getting America off of oil, isn't the same as seeing today's reality. A charging infrastructure remains entirely theoretical. And theories won’t make enough Americans take the financial or psychological leap into electric cars. And even if that charging network existed, that still means hanging out at the electric-car station for three or four hours at minimum to get enough juice to travel another 100 or 120 miles. Better tell grandma to keep the oven warm.

That doesn’t mean I can't see the many upsides of EVs. But I’m also realistic. Cars like the Leaf, for now, are viable mainly as second cars for suburbanites who have handy garages in which to juice them up. Even green-minded, big-city apartment dwellers, potentially an eager audience for EVS, will balk at buying one, lacking any convenient place to charge.

Over the next four days, the Volt will make stops in Little Rock, Ark.; Nashville; Roanoke, Va.; Washington, D.C.; Frederick, Md., Philadelphia; and finally New York. Followers can check out their progress, however fossil-fueled, at sites including @ChevyVoltTwitter and Chevrolet Volt Facebook. If you're a Volt fan, you might offer a friendly wave as they go buy. Or if you prefer pure EVs like the Leaf, perhaps another form of salute.