Am I seriously asking this question? Of course not. But Hugh Hewitt is.
http://www.weeklystandard.com/Content/Public/Articles/000/000/004/233uylts.asp
The inevitable backstab blog has to be on some political consultant's mind. Get it started and growing as a pro candidate X blog. Build an audience via tried and true techniques --including the purchase of blog-ads-- and then, late in a campaign, have the blog turn on candidate X. If any of the high profile lefties at work today--the Daily Kos or Atrios, for example--were to suddenly turn on Kerry, citing implausibility fatigue, for example--that would be news and a blow to Kerry. Could Kos really be working for Rove? The costs of starting a blog are so low that the mischief potential is quite high.
Methinks that Hewitt overestimates the power of the blogger a bit, even a well-known one.