I found the metaphor I needed!
It's a job interview: If you were applying for a position, and you knew who the other applicant was, would you spend your whole interview talking about how terrible the other applicant would be and pointing out the problems with his or her resume? Or would you spend your interview talking about how great you would be for the job?
In the endless interview that is the presidential race, Obama is doing a great job of focusing on what he would bring to the position. But all his friends are calling the HR department to point out how much the other candidate sucks. And the folks in HR (=the American public) are saying, "We like this guy, his resume is solid, he's a great interview -- but what's up with his friends? They're acting like jerks. If we hire him, will we have to work with them?"
In the endless interview that is the presidential race, Obama is doing a great job of focusing on what he would bring to the position. But all his friends are calling the HR department to point out how much the other candidate sucks. And the folks in HR (=the American public) are saying, "We like this guy, his resume is solid, he's a great interview -- but what's up with his friends? They're acting like jerks. If we hire him, will we have to work with them?"