can a character tk someone that is carrying an object?

Sure. Unlike the rules for flying (which specifically say that you can't do that), TK doesn't have any restrictions on moving characters.

In fact, technically, with the wording of the TK power alone you can TK any character under any circumstances (as long as they are adjacent to the TK-er). Only upon reading the specific rules for Giants, Big Figures, etc do you see lines like "this character can not be moved by Telekinesis".