Artur Davis, the former Democratic congressman from Alabama, gave an excellent speech tonight at the Republican National Convention. Although it was ignored by MSNBC, it might have been the best speech of the evening. It was particularly interesting given the fact that Davis' last convention speech was the one in which he introduced his party's nominee, Barack Obama. Next week, Democrats will feature their own party-switcher -- Former Republican Florida Gov. Charlie Crist. He'll probably have a hard time topping Davis. He'd surely have a hard time topping Zell Miller, the Democratic senator who spoke at the 2004 convention. He never switched parties, but Miller sure gave a memorable speech.