One inherent problem with pure-electric cars is that it completely ignores the fact that electricity usually isn't very clean to produce. In fact, the argument could easily be made that a gas-powered kinetic energy generator (i.e. the engine in an automobile) is a hell of a lot more efficient than having a gas-powered electrical energy generator shove electrical energy into a battery and having that power an electric motor.

Hybrid cars are definitely much more efficient than either method, in any case, as evidenced by the current hybrid cars (which are basically normal petrolmobiles with a generator-motor pair instead of a normal engine) getting ungodly fuel efficiency.

Of course, pure-electric cars are probably overall more efficient than pure-gasoline ones, but they're certainly not pollution-free - last I checked, most places in the country still rely on fossil fuel electricity generation (solar and wind are too expensive, and nuclear is too untrusted).