The alarm was first raised when Web-based campaign group Media Matters for America became suspicious at a 'soft question' Mr Gannon put forward at a White House press briefing. Investigations by the group revealed that Mr Gannon, who worked for the Talon News agency, run by Bobby Eberle, had lifted chunks of writing from Republican party and White House press releases.
Mr Eberle is also president of Texas-based Conservative campaign organisation GOPUSA.
On top of this, two Democrat representatives are calling for an official investigation into claims that Mr Gannon also had access to a confidential CIA document involved in the Valerie Plame scandal - an undercover agent whose name was leaked.
Further digging by Media Matters revealed that Jeff Gannon was a pseudonym used by James Guckert, and the story was then picked up by a network of bloggers, including DailyKos and Eschaton.
They discovered that James Guckert was the registered owner of JeffGannon.com - along with Hotmilitarystud.com, Militaryescorts.com and Militaryescortsm4m.com.
Blogger, political consultant and former journalist John Aravosis has used his blog to 'synthesize the mounds of data' unearthed by bloggers in the GannonGuckert episode.
The mainstream press are still missing the big story, said Mr Aravosis, because the more salacious parts of the story are 'too personal' to report.
"An anti-gay conservative GOP writer has had clients dealing with gay escort services and gets immediate access to the family-values president of the United States and internal CIA documents concerning one of the biggest scandals of this administration. No story there!"
Mr Aravosis told dotJournalism that bloggers were better placed to investigate Mr Gannon's background than mainstream journalists.
"Mainstream journalists can't afford to tick off the White House, but those of us in the blogger world couldn't care less about what George Bush thinks of us," he said.
"We know we won't be getting passes to the White House any time soon."
In an interview with Editor & Publisher, Mr Gannon would not say whether he saw the confidential CIA files. He said that the sexually oriented sites were registered by him five years ago for a private client, and denied that anyone in the White House press office had planted or suggested questions to him.
Mr Gannon resigned from Talon News on 8 February. A message on his site states that he has decided to return to private life out of consideration for his family.
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