In 1832, horse racing was by far America’s most popular spectator sport. So when horses named Andrew Jackson and Nullifier appeared at the same racetrack in Richmond, Virginia, thousands of people saw their sporting and political interests overlap. The horses’ names reflected the most divisive political debate of the year, a constitutional crisis over “nullification.” At issue was whether the state of South Carolina could refuse to abide by a federal import tax backed by President Andrew Jackson.