Can I move a range of notes over by a beat to correct an error?

I have a problem in that I wrote out about 8 measures but forgot that the song started on an upbeat. So essentially, my song starts in the wrong place. It currently starts on the 1 beat (4/4 time), when it should start on the 4th beat of the prior measure. In all, 8 measures need to be shifted over to the left by the duration of one quarter note. Is there any way to do this? Or do I have to start over?