"I'm sure he [Obama] is very patriotic," McCain said. "But his relationship with Mr. Ayers is open to question. ... If you're going to associate and have as a friend and serve on a board and have a guy kick off your campaign that says he's unrepentant, that he wished he had bombed more."
The "wished had bombed more" remark referred to something Ayers said in 2001 when asked about the bombs he admitted planting during his years as a radical.
Ayers told The New York Times: "I don't regret setting bombs. I feel we didn't do enough."
Later, Ayers explained that what he meant was that the anti-war movement did not do enough to try to stop the war in Vietnam.
Neither Ayers nor his wife, Bernadette Dohrn, another former Weather Underground member, were ever convicted of any criminal charges related to the violent acts they were said to have committed.
What was known about Obama and Ayers' relationship was that Obama attended a political function at Ayers' home in Chicago in 1995. They served together on a couple of non-profit community service boards. Ayers contributed $200 to Obama's state Senate campaign in 2001.
But the McCain campaign kept suggesting there was more to it. Whenever McCain officials were asked what more they knew, they would say only that they were certain the relationship was closer than Obama described it.
McCain's senior advisers, Steve Schmidt and Charles Black, kept saying that at some point, McCain would attack Obama over Ayers. Obama's controversial former minister the Rev. Jeremiah Wright was off-limits, they said, but not Ayers because Ayers was a terrorist.
On occasion, McCain campaign officials would bring up Ayers. In May, with McCain under fire from Obama and others for having former and current lobbyists in his campaign, his campaign fired back by citing Ayers.
"Just a few years ago when Barack Obama was beginning his career in politics, he was launched it a the home of William Ayers, an unrepentant terrorist," said Tucker Bounds, a McCain campaign spokesman. "If Barack Obama is going to make associations the issue, we look forward to a debate about Senator Obama's associations."