This will be a single digit race. Harrison will mobilize unlikely black voters but there are not enough Latinos, Asians, and progressive whites to close the gap.
This is my take too. I say Harrison does slightly better than Smith did by getting out more black voters, but not much more. I'd say 53-47 is about as close as it'll get.
Does your SOS office keep track of the race of registered voters? I was looking at 2016 SC Exit Polls and it said black voters only made up 19% of the electorate (but they are 27% of the population). Does that seem accurate? In comparison black people are about 32% of the pop in GA but we are usually 28-30% of the electorate.