Uh, the Jetta TDI gets 62mpg in practice (someone did a 5,000+-mile trip going counterclockwise, west across the northern U.S. and then east along the southern U.S), while its gasoline counterpart boasts 32mpg on the highway and 27mpg in the city.
In most of the U.S., you need ULSD. Here on the east coast, gasoline costs $1.55 now and diesel is going for $1.75. A 300 mile tank on my Mazda 3S with the 2.4L (averaging a good 25-28mpg) costs $18 now; a few months back it was still around $25, when gas was $1.92. Surprising me with these low fuel prices.
BTW: At CA electricity and gas prices you're claiming that a 100% efficient Tesla, consuming only 62MJ of electricity, will make that trip, but a gasoline powered car would require 1180MJ to make the same trip. That is a 5% fuel-to-travel efficiency, not the 14-30% [fueleconomy.gov] that is known.
Yes but California is a lunatic state. See also: Texas, where some cities have electricity for under 5 cents per kWh.