Over the last three months, Mr. Obama has quietly consulted Mr. McCain about many of the new administration’s potential nominees to top national security jobs and about other issues — in one case relaying back a contender’s answers to questions Mr. McCain had suggested.

Mr. McCain, meanwhile, has told colleagues “that many of these appointments he would have made himself,” said Senator Lindsey Graham, a South Carolina Republican and a close McCain friend…

Some Senate Democrats have complained that Mr. Obama failed to seek their contributions about certain appointments — notably Leon E. Panetta as director of the Central Intelligence Agency. But the Obama transition team has consistently sought advice and feedback from Mr. McCain, the ranking Republican on the Armed Services Committee, on national security appointments, Mr. Emanuel and Mr. Graham both said.