As this blog has noted before, the generation that came of age in the Sixties was a generation that faced crisises that divided America, not united America. The civil rights movement, the women rights movement, and the war in Vietnam all divided Americans rather than brought them together. This is in contrast to the crisises faced by that generation's parents, such as the Great Depression, WW II, and the Cold War. These crisises, which involved all of the Society facing a common threat, brought Americans together.
One result of the Sixties was bitter inter-generational conflict. This was carried over into politics. Look at the first two baby-boomer presidents, Clinton and Bush. They are two different political personalities with two very different philosophies.
One advantage that Barack Obama may have is that while he is technically a baby-boomer, he was born very late in that generation. This means that he wasn't caught up in the whole Sixties experience. He wasn't part of the bitter debates that marked that period. This means that he has a whole different outlook on American politics.
This also may mean that he can transcend the bitter divisions of that era. This may be why he is enjoying a lot more support than people thought he would enjoy. Americans may instinctively recognize that his election would represent a different approach to politics.
All of this is not meant as an endorsement of Obama. Rather it is an attempt to figure out where his supporters are coming from and why he has strong support.