Obama's involvement in voter registration efforts in Chicago have been used to trumpet his activities in the community and his support for democratic ideals. It would be great if he hadn't done the exact opposite in his run for state senate. In his run for state senate, he blocked voter petition signatures of his three major Democrat opponents. By blocking signatures, he was able to deny each of the opponents' petitions to get on the ballot. Obama ran unopposed in the primary thus removing voter choice.
The catch is that, yes, everything he did was by the books. But one could argue it was far from the spirit of the rules and not sporting or honorable. Definitely not democratic. It was as the Chicago Tribune refers to it, "bare knuckle" politics.
It is no surprise that Obama has recently dropped out of the public financing, contrary to his previous positions on the matter. He makes the argument that he's doing it because the system is broken. When, honestly, it's all about strategy. By dropping out of public financing, Obama can take advantage of his large support network for raising funds. Basically, he's going to look to beat McCain on the money front.
As others have posted, you don't get to where McCain or Obama are by being the images that are painted for us.
Folks should not be all that surprised by how Obama voted for the FISA amendment. It was possibly a good strategic, non-idealist thing to do. McCain has an opportunity to attack it, but I'm not sure abstaining gives McCain much credibility on this issue either. ;-)