At Politico, Maggie Haberman writes about GOP activists who disagree with strategist Karl Rove: "For the first time in a dozen years, Karl Rove’s critics smell blood."
Actually, journalists have been using this figure of speech for a long time.
In 2007, Chris Matthews said: "Democrats are frustrated that Rove wasn't indicted in the CIA leak case, but now that he's been implicated in the firing of those US attorneys, it looks to some people as though Democrats are smelling blood."
In 2007, Wolf Blitzer said to James Carville: "And Democrats really are smelling blood right now, James, as you see. And their eyes are specifically focused not all completely on Alberto Gonzales, but on Karl Rove."
In 2005, The Financial Times reported: "The dust-up over Karl Rove's role in the Valerie Plame leak affair has the usually docile White House press corps smelling blood."
In 2004, Stuart Taylor wrote in National Journal: "The many reporters who see the Bush White House as a den of dissemblers smell blood in the water. And Washington is seething with speculation that the suspects may include Rove, Libby, or perhaps other top officials."
In 2003, Howard Fineman told Chris Matthews on Hardball: "And one of the really interesting things politically here is that one of the names that Ambassador Wilson mentioned is that of Karl Rove, who's the president's longtime political aide, really helped to architect the president's political career. That's the blood in the water that is especially exciting the sharks around town"