I know some intellectuals are put off by Obama's rhetoric, complaining that his campaign represents the victory of "style over substance". But I think this is mistaken. The complaint would only be legitimate if his rhetoric were serving to mask a genuine lack of substance, but closer examination reveals that in fact there is no such lack. Instead, we have a substantial candidate who, when campaigning, plays up style for the sake of motivating and winning over the electorate. Isn't this just good politics?
In an ideal world, of course, the electorate would not be swayed by non-rational influences. Wonkish talk about increasing transparency by RSS-ifying government data should suffice to "uplift" and motivate support. But this is not an ideal world, populated by ideally rational citizens. People are influenced by a nice suit and haircut, personal charisma, and eloquent rhetoric. So an effective politician will play to these biases in order to shore up support. Would it be better if they didn't? I don't see how. They should want to reform the system to make it more responsive to reason, of course. But for as long as the flaws still exist, it would seem imprudent not to take advantage of them. (Their opponents certainly will.)
N.B. This only holds within moral limits. I certainly don't want to excuse deception, for example. But there is a clear and principled distinction here. Rhetoric and such are rationally neutral, making us neither more nor less likely (in general) to reach the truth. Deception, on the other hand, is anti-rational, a positive obstruction to informed decision-making.
So I don't see any grounds for objecting to politicians using all morally permissible (even if non-rational) means to garner support. Granted, this just shifts the question to which methods are morally impermissible. But I doubt that anyone could seriously contend that rhetoric belongs on the blacklist.