He was in Trinity United Church of Christ, but not of it, not sharing the liberation theology that energized Jeremiah Wright Jr. He is in the United States Senate, but not of it. He has not had the time nor the inclination to throw himself into Senate mores, or really get to know more than a handful of his colleagues. His Democratic supporters there speak of him fondly, but vaguely.

And so it goes. He is a liberal, but not fully liberal. He has sometimes opposed the Chicago political establishment, but is also part of it. He spoke at a rally against the Iraq war, while distancing himself from many antiwar activists.

This ability to stand apart accounts for his fantastic powers of observation, and his skills as a writer and thinker. It means that people on almost all sides of any issue can see parts of themselves reflected in Obama’s eyes. But it does make him hard to place.

When we’re judging candidates (or friends), we don’t just judge the individuals but the milieus that produced them. We judge them by the connections that exist beyond choice and the ground where they will go home to be laid to rest. Andrew Jackson was a backwoodsman. John Kennedy had his clan. Ronald Reagan was forever associated with the small-town virtues of Dixon and Jimmy Carter with Plains.

It is hard to plant Obama. Both he and his opponent have written coming-of-age tales about their fathers, but they are different in important ways. McCain’s “Faith of My Fathers” is a story of a prodigal son. It is about an immature boy who suffers and discovers his place in the long line of warriors that produced him. Obama’s “Dreams From My Father” is a journey forward, about a man who took the disparate parts of his past and constructed an identity of his own.

If you grew up in the 1950s, you were inclined to regard your identity as something you were born with. If you grew up in the 1970s, you were more likely to regard your identity as something you created.

If Obama is fully a member of any club  and perhaps he isn’t  it is the club of smart post-boomer meritocrats. We now have a cohort of rising leaders, Obama’s age and younger, who climbed quickly through elite schools and now ascend from job to job. They are conscientious and idealistic while also being coldly clever and self-aware. It’s not clear what the rest of America makes of them.

So, cautiously, the country watches. This should be a Democratic wipeout. But voters seem to be slow to trust a sojourner they cannot place.