I believe the departed reached an all time political high when they were able to elect one of their own to the Senate from Missouri. Why, even the dead from East St. Louis got to vote in that one, due to a Dem judge keeping the polls open long enough for them to shamble across the Mississippi.
The dead vote routinely in big cities like Baltimore, Philadelphia, Chicago, Seattle, etc. I don't know why anyone would be surprised to find the same thing in Memphis or St. Louis.
The GOP usually isn't even trying to win those elections; it only becomes an issue when a GOP candidate really wants to win. Which is seldom.