“There seems to be a movement on the local and state level,” Scott said, of black Democrats who want “to align with their values” rather than with their history as Democrats. “We’ll continue to see that shift.” Artur Davis, a former Democratic congressman from Alabama, has been a Republican for only a few months. But his speech tonight at the Republican convention is important because he reflects a major theme of Mitt Romney’s campaign against President Obama and another theme promoted by the GOP. The Romney theme is that it’s okay to have changed your mind about Obama. Davis, an...