Can Bush pardon Ted Stevens?

We were talking about this in my office and one person said that Stevens wouldn't be pardoned because he has to exhaust all legal possibilities first, such as an appeal, in order to be pardoned. By the time Stevens has exhausted all legal possibilities, Bush would be out of office. But I thought that giving a pardon is the exclusive right of the Executive Branch and that there aren't restrictions on how and who he pardons. Do you know the rules regarding this? Is my co-worker right?