That's a good question, I don't know the answer to that. One thing to include though is transmission loss to get the electricity to the place it's needed. And at the same time of course include the energy used to get petrol to a gas guzzling car. In other words, the comparison needs to be fair, and that doesn't sound like an easy analysis. I'd be interested to hear from anyone that knows more about this.
You're absolutelly right, just a small caveat for the 60% figure: most well-maintained plants capture between 35% and 40% of heat energy. Peakers can reach 35% too. Pulsed coal and new gas tech can get to 50-60% in ideal conditions. Also, most of these techs are new and are available on recently-build plants. That 60% could be as low as 45%.
Still at least twice as effective as ICEs.
However, a 2-tons electric car compared to a 800kg ICE? without taking into consideration the wear on infrastructure and on singular parts of the vehicle, i still think you are in comparable zone.
The most important point, IMO, is that localized emissions do the most harm. Even if the emissions were equal, keeping pollution out of the urban core will literally prevent (or defer) millions of cases of lung cancer etc. This paper quantifies the social cost of atmospheric release:
https://link.springer.com/article/10.1007/s10584-015-1343-0
It's really hard to make these comparisons because environmental impacts aren't fungible. The emissions from building and running an electric car might be more CO2 overall but the CO2 is being emitted at a few large factories and could be more easily captured than from individual cars.
ICEs also emit lots of other pollution in the middle of cities, including noise pollution. Electrics would cut down on those or emit them around the factory instead of downtown.
Transmission losses are not significant in most cases. Your assertion that electricity from fossil fuel power plants is somehow worse than inefficient ICE cars is completely wrong.
Depending on transmission losses, yes. Theoretically, power plants could also have better exhaust scrubbing and carbon capture, but most currently don't.