Until I can drive 40 miles each way (to and from work) with the windshield wipers, headlights, and heated AC (aka defroster) running, an electric car does me no good. If there was a mandate to produce only electric vehicles come 10 year's time, I'd plan on buying a new gasoline car in the 9th year, which I'd be able to drive for a long time.
Here's a prediction: Electric cars will become common in Germany at least 20 years before they are common here.
Why Germany? Well, first, it's small. Germany is about the size of California, but more compact. There are some 85 million people -- roughly 1/3 the population of the USA. So the population density is pretty high. More importantly, it's very urban. They don't have suburbs, let alone exurbs.
But this part is really critical to my logic: Germany has no oil fields. One of the contributing causes to Germany losing WW2 was lack of oil to make the war machines go. None of the world's major oil companies are German. In other words, they have no "big oil" industry to mess in their politics, and they have a national security incentive to minimize oil consumption (their fuel tax is something like $6/gallon).
And Germany has automotive expertise -- Porsche/VW/Audi, Mercedes, BMW. With that $6 tax you know there would be a might good market for highly fuel efficient vehicles. That's why I don't buy any of the conspiracy theories on why cars don't get better fuel economy.
Looking at 2008 Census data, I see that of 138 million people who work outside the home, 124 million travel by automobile, and 25 million of them (about 20%) had commutes of 35 minutes or more. 70 minutes of daily travel doesn't tell us how many miles they go, but it tell us how long the headlights, wipers, and AC/heater have to operate. Electric cars probably make sense for a lot of people, and they could work really well in some parts of the country, but they don't make sense for everyone.