At the core of that article that began on the front page are two anonymous sources. These sources, according to the article, say they confronted McCain in 1999 with their concerns that he was risking his career by interacting with Vicki Iseman. As a columnist, I’m an independent operator, speaking for myself alone. I have no idea who those sources are. But they are bound to come from the inner circle of the McCain universe. The number of people who could credibly claim to have had a meeting like that with McCain in early 1999 is vanishingly small. I count a small handful of associates with that stature, including Davis and Weaver. There is nobody in that tight circle unaffected by the hostilities that emanate from the rift.

Thursday, as McCain was fervently and completely denying the allegations of an affair with Iseman, people in all quarters of the McCain universe were vehemently denying it, too. But even on this embattled day, they broke down into rival camps over the identity of the sources.

Many in the Davis camp argued Thursday that Weaver must be the chief anonymous source, and that he had roped in one other confederate. He’s had a hard life, they said, and is driven by demons.

Weaver countered by telling reporters that he retains enormous affection for McCain and desperately wants him to become president. Moreover, Weaver had been trying to get back into the fold. There is no way he would be an anonymous source against McCain. Some closer to Weaver theorized that the sources must be former McCain campaign elders from 2000 who worked for rival campaigns in 2008.

I checked that possibility out, and it doesn’t hold water. But while calling around to a dozen senior McCain friends and advisers Thursday, what struck me was the enormous tragedy of the rift. They all love McCain. They all say it is absurd to think he abused his power in the way that is alleged. But the rift is like some primal sore. It affected every conversation I had Thursday, as it has infected McCain efforts again and again over the past many years.

At his press conference Thursday, McCain went all-in. He didn’t just say he didn’t remember a meeting about Iseman. He said there was no meeting. If it turns out that there is evidence of an affair and a meeting, then his presidential hopes will be over. If no evidence surfaces, his campaign will go on and it will be clear that there were members of his old inner circle consumed by viciousness and mendaciousness.

But lingering over everything is the bitterness of the rift, which has caused duplicity and anger to seep into the campaign of this fine man. The poisons have yet to be drained.