Columbia statistics and political science professor Andrew Gelman
argues that the red state / blue state divide can be explained by the voting habits of each state's wealthiest
residents. He and his researchers have found that rich people in poor states are more likely to vote Republican, while rich people in rich states tend to vote Democratic. Andrew Gelman is the co-author of the November 2005 study "Rich State, Poor State, Red State Blue State: What's the Matter with Connecticut?"