Doubtful, unless you've secretly developed perpetual motion.
Nope - almost absolutely guaranteed. Automotive engines, required to operate over wide speed ranges from idle to a few thousand RPMs, are terribly inefficient in design. Generators, on the other hand, can be designed to operate in a sustained manner over a very narrow RPM range (+/- .5% in the case of utility power generation). With very constrained operating conditions, the generators can be made much more efficient - or rather, they can be designed such that they operate exclusively in their most efficient operating range. Even a small gasoline generator will be more efficient in providing power than an automotive engine over its operating range. The trick is that an electric motor doesn't really care what RPM it is operating at as far as efficiency is concerned, and the speed of the motor is completely decoupled with the speed of the generator. Adding a battery does add a step with losses (charging and discharging the battery is not 100% efficient), but those losses are still small compared to the loss in efficiency from using an engine, and using utility-scale power generation is even more efficient than a small generator, making up for the losses. Additionally, the electric vehicle can use other tricks to save or regain energy, such as regenerative brakes which use the vehicle's kinetic energy to recharge the battery when slowing - this is relatively simple if the electric motors are at each wheel, since a generator is simply an electric motor being driven by the shaft.
Overall, providing a given amount of energy to the wheels generally takes less fuel if provided in the form of electricity as opposed to mechanically transmitted from a gasoline/diesel engine. The electrical system is of course more complex, but mechanically the vehicle can be much less complex, as the transmission and engine can be eliminated and an electric motor has very few moving parts.
Mike