Next to the cash register of the Bob Moates Sport Shop in Chesterfield County, near the tanks of live bait, is a sign telling customers about the Bloomberg Gun GiveAway. For every $100 that customers spend at the sporting goods and Civil War-relics dealership, they get one ticket for a chance to win a gun in a drawing held by the Virginia Citizens Defense League. The rules include a list of who is eligible to win, as well as a list of who isn't, among them New York Mayor Michael R. Bloomberg and his immediate family members. When Bloomberg began...