I have biases against the South. I do not have bigotry against southerners, but I do have different values than what are traditionally considered Southern values.
I associate the South with a few things that I don't particularly care for.
A Christian myself, I do not like fundamentalist Christianity. I disagree with most of the principles of fundamentalist Christianity.
1. Theologically. I do not accept "Sola Scriptura," I do not accept a literal interpretation of Genesis, and I do not believe "This is my body" and "This is my blood" to be symbolic.
2. Socially. I like gay people. I also like non-christians, Catholics, and feminists.
3. Intellectually. I accept evolution.
4. Politically. In general, Christian fundamentalists hold political views that are not my own. Among other things, I'm a strong advocate of separation of church and state.
I associate the South with racial oppression, injustice, and inequality. The South should not be the scapegoat for the entire nation's history on race, but the South does have a pretty ugly history that includes slavery, the KKK, Jim Crow laws, segregation, and a great deal of racism and violence.
Should I consider this to be the past, history, no longer relevent? I don't think so. Robert Byrd was a member of the KKK and he filibustered Civil Rights legislation, but he continually gets re-elected in West Virginia (I realize West Virginia has a complicated history that may or may not make it part of "the South"). Strom Thurmond was a segregationist presidential candidate, but he was elected to congress in South Carolina into the 1990s. Trent Lott said that the U.S. would have been better off had it elected the segregationist Thurmond, and he still easily gets re-elected in Mississippi. This is just a guess, but if a U.S. Senate candidate in a non-Southern state had a history as a member of the KKK, a history as a supporter of segregation, or suggested the U.S. would be better off had a segregationist been elected president, his/her political career would probably be over. And many southerners continue to take pride in the Confederate flag: it is displayed at the South Carolina statehouse grounds, it is part of Mississippi's state flag, and in several southern states you can get a license plate featuring the confederate flag. I am not convinced by arguments that this is a celebration of "heritage" or "history" separate from a history that includes terrible (and official) racial oppression.
These are two central areas in which my values are at odds with southern values, or at least what I associate with southern values.