WASHINGTON (CNN) -- John Kerry has hired an Internet-savvy Democrat to run his presidential campaign's online communications, a move that raises new questions about the link between his campaign and the independent groups that run TV ads on his behalf. Zach Exley, the director of special projects for the MoveOn PAC, is going to the Kerry campaign to become its director of online communications and organization. Exley also worked during the Democratic presidential primary for Howard Dean, helping Dean set up his web-based organization. MoveOn has spent roughly $17 million on ads since it started running its "misleader" campaign against...