A friend sent me a link to a very good post on how PR firms should approach bloggers. It's sort of a "what to and not to do list". While aimed at people doing corporate PR, it is certainly applicable to campaigns as well. If you're thinking of opening your campaign up (and you should be), it is sage advice for you to follow.

Blogs are community-oriented web properties where readers are encouraged to engage in conversation. It's not supposed to be a one-way street like the mainstream media. This is why it's important to keep an informal, conversational tone when responding to the blogger and readers. Constructed and flat statements will be called out as "spin" and you will be accused of not addressing the issue. Remember, companies and organizations are made up of humans, so act like a human, not a computer delivering a line of programming.

This is well worth a read for anyone who interacts with bloggers - be it the candidate or the communications guy.