1. Yankees, more African Americans and immigrants moved in and changed the demographics
Immigration is the only thing that really changes the Confederate states. As we've found out the native white population of the South is the home base of the Tea party.
"Because of immigration in the late 20th century and early 21st century, there are rapidly growing populations of Hispanics, with Salvadorans and Mexicans more concentrated in the Northern Virginia suburbs of Washington, DC, and Puerto Ricans more concentrated in the Hampton Roads area. There is also a significant Asian population in Northern Virginia. As of 2005, 6.1% of Virginians are Hispanic and 5.2% are Asian. Northern Virginia has the largest Vietnamese population on the East Coast, with about 48,000 Vietnamese statewide as of 2007. Their major wave of immigration followed the Vietnam War. Hampton Roads has a sizable Filipino population with about 45,000 in the area, many of whom have ties to the U.S. Navy. Virginia also continues to be home to eight Native American tribes recognized by the state, though all lack federal recognition status. Most Native American groups are located in the Tidewater region."