There's enough buzz about the possibility of some conflict with Iran, either US or Israel initiated that we have to take this very seriously. Once conflict starts, this could give McCain, with his military credentials, at the least, a claim to having better experience, even if his military experience consists of being a crashed pilot and prisoner and in graduating in the lowest one percent out of over 800 students at the Naval academy.
To balance McCain's dubious claim of military experience, Obama will have to bring in a VP with military experience. Jim Webb makes the most sense to me. As a Virginia senator, he'll reel in Virginia as a formerly red state turned blue. Born in Missouri, he could help Claire McGaskill bring in that state.
Also a Naval Academy grad, he received Superintendent's Commendation for outstanding leadership contributions while a midshipman.
His bio reports:
First in his class of 243 at the Marine Corps Officers' Basic School in Quantico, Virginia, Webb served with the Fifth Marine Regiment in Vietnam, where as a rifle platoon and company commander in the infamous An Hoa Basin west of Danang he was awarded the Navy Cross, the Silver Star Medal, two Bronze Star Medals, and two Purple Hearts. He later served as a platoon commander and as an instructor in tactics and weapons at Marine Corps Officer Candidates School, and then as a member of the Secretary of the Navy's immediate staff, before leaving the Marine Corps in 1972.
Webb received his J.D. at Georgetown University Law Center in 1975. He served in the U.S. Congress as counsel to the House Committee on Veterans Affairs from 1977 to 1981. In 1982, he first proposed, then led the fight for, including an African American soldier in the memorial statue that now graces the Vietnam Veterans Memorial on the National Mall. In 1984, he was appointed the inaugural Assistant Secretary of Defense for Reserve Affairs. In 1987, he became the first Naval Academy graduate in history to serve in the military and then become Secretary of the Navy.
When Webb leaves the senate to become VP under Obama, the Democratic governor of Virginia will be able to replace him with a Democrat.
Wesley Clark is another viable candidate, but I just don't see him as likely as Webb, since he was a strong Hillary backer and would probably not help to bring in any state.