Gandalf was a politician and a bit of a charlatan that (in the books) didn't do much magic that could be verified by anyone else. Sure he theoretically did a lot of things off-screen, but that's assuming he's a trustworthy narrator. He had some flash-bangs that scared off goblins. He had a fast horse and a way of convincing people to do what he wanted. He had a staff that he broke as a one-time thing to bring down a bridge. The fight with the Balor? Who knows what really happened or if Gandalf's version is at all accurate?
But for the most part? When things really got rough, someone else took all the risks. He was good at talking people into doing incredibly stupid and risky things like sending a hobbit along with a small group of dwarves off to face a dragon that had absolutely no chance of success. Merry and Pippin working with the Ents? Gandalf took all the credit even though he had nothing to do with it. Minas Tirith? He kept talking about how any moment now he was going to let loose and everyone needed to watch out! But then he never actually did anything.
But I think Gandalf being a politician was kind of the point. Frodo was the every-man commoner summoned to go to war while the politicians moved them around like pawns on a chess board.
P.S. Yes, I know in the background books he's a malar(sp?) and all that fun stuff. I'm talking about the impression I got from reading The Hobbit and the LOTR trilogy when I was young.
