Steve Duprey, a longtime friend of McCain’s and a senior adviser in his 2008 campaign, said the senator respected Obama, even if the two were never particularly close and wounds from their race were raw for years.

“I think it is John McCain imparting a lesson in civility by asking the two men who defeated him to speak, as an example to America that differences in political views and contests shouldn’t be so important that we lose our common bonds and the civility that is, or used to be, a hallmark of American democracy,” Duprey said.

David Axelrod, a senior adviser to Obama in his campaigns and in the White House, said the clear message McCain is sending is “about our shared heritage, our shared trust of this democracy that transcends party and transcends tribe.”

“It really does animate his message of national unity,” Axelrod said. “There is a kind of poetry to it that he wanted his two erstwhile opponents to eulogize them.”