Blood In The Water Meaning

Example : 1983: Michael J. Robinson and Margaret A. Sheehan, Over the Wire and on TV,  The first reason Powell gave to explain Carter's press miseries was the idea of "blood in the water"—that more bad press goes to those who have just had bad press. Almost nobody in main-stream politics is as likely as a fourth-year incumbent to have just come off a stint of bad press.1995: John Gallant, Network World (29 May),  But Justice won the Intuit round, and now Microsoft-baiters want to block deployment of the Microsoft Network. As a recent article in the Wall Street Journal aptly noted, competitors sense blood in the water.2004: Gardner Dozois, The Year's Best Science Fiction: Twenty-First Annual Collection,  [The] Democrats smell blood in the water. Twelve long years sitting on the sidelines. Twelve lean years. Twelve hungry years.