Despite the press having talked about lots of rumors, below is the one I am remembering. I don’t remember McCain personally ever acknowledging that the discussion took place, that the offer was made and he turned it down. There were also rumors/stories that it was McCain who approached Kerry, but that was denied saying that maybe a staffer talked to somebody, sometime.
http://www.freerepublic.com/focus/f-news/1151968/posts
WASHINGTON - Republican Sen. John McCain has personally rejected John Kerry’s overtures to join the Democrat presidential ticket and forge a bipartisan alliance against President Bush, The Associated Press has learned.
(snip)
“Senator McCain categorically states that he has not been offered the vice presidency by anyone,” said McCain’s chief of staff, Mark Salter, who would not confirm the officials’ account.