A detailed list breaking down the most recent data involving registrations of battery EVs in the US, compared by side-by-side by state.
electrek.co
statistically speaking, you'll find some. now, you would have to do some additional whittling down of the target audiences at a nascar race and a state fair, however, the Texas state fair is probably the largest, and I'm assuming that some of those 50k+ EV owners will be going.
I'm actually surprised at the numbers for NJ. The eye test, at least where I live, would suggest that there are a whole lot more than 30k EV's on the road. But that's probably locally biased.