Here's an interesting analysis of the three leading Democrats' speaking styles: Group News Blog: Declaration – Request – Promise::Lead – Lobby – Legislate. It's a long post, but here's a taste of the key part:
Executive = Declarations: bring forth, generate something new, lead.
Manager = Requests: please do x by time y with condition of satisfaction.
Worker = Promises: deliver competent performance in a domain, over and over.
And never the twain shall meet.
Let's walk it back to our Presidential candidates.
One speaks in declarations, inspires, leads.
The second requests you elect him to fix problems, lobbies for a change so he can fix the system.
The third talks of her competence and experience, promises she will do what she's always done, and has the policy plans and papers to prove it.
Leader. Manager. Worker.
Obama is breaking out now because he speaks the language of a leader.
Watch him at the 100 Club Dinner in New Hampshire.
He's not making promises, even when the words coming out of his mouth are a promise. ALL of everything he's saying is a declaration, a future which is true now because he speaks it.
Edwards, he argues, uses the language of a manager: I can fix things, but only if you elect me. So it’s a request, rather than a declaration. Clinton users the language of a worker, promising competence and skill. But these are promises while Obama says it it and makes it so.
I’m not sure if I’m convinced, but it’s interesting.