Believe it or not, even the federal government fires employees for electioneering in the workplace or via government equipment or gov’t vehicles. Those are violations of the Hatch Act. (Having a political Bumper sticker on your personal car in the Govt parking lot is OK). I’m not suggesting that the Democrats don’t violate the Hatch Act on a daily basis, but if some Kool-Aid drinker uses his govt computer to spam his co-workers with “Re-elect Obama” email, and it gets reported, that worker is going to get fired.
However, if you use said personal car to conduct any official government business, it is not.