Ryan Lizza writes a mammoth of a bio piece in The New Yorker on Obama from 1991 until 2004, a part of his life not dwelled upon in his books or speeches. It's very good. It takes a fiercely pragmatic take on Obama's early political career and is not very generous regarding the motives behind Barack's big stances: his religious conversion, his opposition to the war, his complicated relationship with blacks and Mayor Daley, etc. Still, it effectively presses a point that really should be pretty obvious by now: that the conventional (and conventionally lazy) media myth of Barack Obama as a pie-in-the-sky, naive carebear of a candidate is profoundly ill-informed. Personally, I don't find it difficult to believe at all that he is a pragmatist in practice even if he's ideologically left of center. In fact, I think that's precisely what many people find appealing.
Then again, I'm pretty forgiving of campaign tactics because I'm of the opinion that a) there's no such thing as a fair fight, and b) if you really believe that you can change things for the better, you are morally obligated to play to win. If a little-used rule allows you to challenge the signatures that a candidate needs to get on the ballot, do it. If the rules state that you can gerrymander the f**k out of your district if your party runs the show on Jan. 1, 2001, then do it. If the rules are unjust, they should be changed outside of election season. The same applies with negative advertising: if your opponent is a douchebag, there's nothing wrong with running an ad calling him a douchebag.
Obviously, there are some tactics that, though legal, are beyond the pale, and every individual has to decide what their own "line" is. I personally think a campaign should remain fundamentally honest, both about themselves and their opponents, so that voters can make an informed decision. That's my line. To me, then, it matters a lot that John McCain calls himself "an early critic of Bush on the war" when he was one of his vocal supporters, while Barack challenging his opponents' signatures (signatures that were in fact found to be inadmissible, I should add) is trivia.