Corcoran, former chief of staff to House Speaker Marco Rubio, had money and energy. But he was fighting to build name recognition against Dennis Baxley and Charlie Dean. Polls showed him lagging.
Over the weekend, a mailer quoted Nancy Argenziano's mother (yes, her mother) about hard feelings in the 1998 House race. "The pain won't go away - and neither will he," Jean Marchese said of Corcoran. That followed a mailer accusing Corcoran of "lies" in the House contest, which Argenziano won easily.
To be competitive, the Crystal River Republican would have to go negative -- or "nuclear" in the words of one of his close friends. There are no plans for him to return to the House, or seek an open House seat.
UPDATE: Corcoran confirmed the news. "As a lifelong Republican, I believe deeply in the principles and values of our Party," he wrote in a statement. "My goal has always been to further those values and principles, and to assure that the District 3 Senate seat was held by a Republican. My desire was that this would be a positive and issue-based campaign. Recent developments have made it clear that this will not be the case." Full statement in comments.