The president is not known to wear a back brace, and it's safe to say he wasn't packing. So was the bulge under his well-tailored jacket a hidden receiver, picking up transmissions from someone offstage feeding the president answers through a hidden earpiece? Did the device explain why the normally ramrod-straight president seemed hunched over during much of the debate? 

Bloggers are burning up their keyboards with speculation. Check out the president's peculiar behavior during the debate, they say. On several occasions, the president simply stopped speaking for an uncomfortably long time and stared ahead with an odd expression on his face. Was he listening to someone helping him with his response to a question? Even weirder was the president's strange outburst. In a peeved rejoinder to Kerry, he said, "As the politics change, his positions change. And that's not how a commander in chief acts. I, I, uh -- Let me finish -- The intelligence I looked at was the same intelligence my opponent looked at." It must be said that Bush pointed toward Lehrer as he declared "Let me finish." The green warning light was lit, signaling he had 30 seconds to, well, finish. 

Hot on the conspiracy trail, I tried to track down the source of the photo. None of the Bush-is-wired bloggers, however, seemed to know where the photo came from. Was it possible the bulge had been Photoshopped onto Bush's back by a lone conspiracy buff? It turns out that all of the video of the debate was recorded and sent out by Fox News, the pool broadcaster for the event. Fox sent feeds from multiple cameras to the other networks, which did their own on-air presentations and editing. 

To watch the debate again, I ventured to the Web site of the most sober network I could think of: C-SPAN. And sure enough, at minute 23 on the video of the debate, you can clearly see the bulge between the president's shoulder blades. 

Bloggers stoke the conspiracy with the claim that the Bush administration insisted on a condition that no cameras be placed behind the candidates. An official for the Commission on Presidential Debates, which set up the lecterns and microphones on the Miami stage, said the condition was indeed real, the result of negotiations by both campaigns. Yet that didn't stop Fox from setting up cameras behind Bush and Kerry. The official said that "microphones were mounted on lecterns, and the commission put no electronic devices on the president or Senator Kerry." When asked about the bulge on Bush's back, the official said, "I don't know what that was." 

So what was it? Jacob McKenna, a spyware expert and the owner of the Spy Store, a high-tech surveillance shop in Spokane, Wash., looked at the Bush image on his computer monitor. "There's certainly something on his back, and it appears to be electronic," he said. McKenna said that, given its shape, the bulge could be the inductor portion of a two-way push-to-talk system. McKenna noted that such a system makes use of a tiny microchip-based earplug radio that is pushed way down into the ear canal, where it is virtually invisible. He also said a weak signal could be scrambled and be undetected by another broadcaster. 

Mystery-bulge bloggers argue that the president may have begun using such technology earlier in his term. Because Bush is famously prone to malapropisms and reportedly dyslexic, which could make successful use of a teleprompter problematic, they say the president and his handlers may have turned to a technique often used by television reporters on remote stand-ups. A reporter tapes a story and, while on camera, plays it back into an earpiece, repeating lines just after hearing them, managing to sound spontaneous and error free. 

Suggestions that Bush may have using this technique stem from a D-day event in France, when a CNN broadcast appeared to pick up -- and broadcast to surprised viewers -- the sound of another voice seemingly reading Bush his lines, after which Bush repeated them. Danny Schechter, who operates the news site MediaChannel.org, and who has been doing some investigating into the wired-Bush rumors himself, said the Bush campaign has been worried of late about others picking up their radio frequencies -- notably during the Republican Convention on the day of Bush's appearance. "They had a frequency specialist stop me and ask about the frequency of my camera," Schechter said. "The Democrats weren't doing that at their convention." 

Repeated calls to the White House and the Bush national campaign office over a period of three days, inquiring about what the president may have been wearing on his back during the debate, and whether he had used an audio device at other events, went unreturned. So far the Kerry campaign is staying clear of this story. When called for a comment, a press officer at the Democratic National Committee claimed on Tuesday that it was "the first time" they'd ever heard of the issue. A spokeswoman at the press office of Kerry headquarters refused to permit me to talk with anyone in the campaign's research office. Several other requests for comment to the Kerry campaign's press office went unanswered.