We are Barack Obama?

What is this “we” that Obama uses all the time? I was just watching him on the most recent Meet the Press where he was using sentences like, “Look, we are running for president of the United States” and “People have the right to know what we will do as president.”

It drives me crazy to listen to. Not only is it grammatically awkward, it is just weird.

Why can’t he say “I” instead of “we”?

Is he speaking collectively? Editorially? Royally?