Yep - easily! Let's say I want to create a duplicate of my "Spa Heaven" item.

First, head to "Items" and click "Copy Items"

Next, click select the auction you'd like to copy from. In this case, it's the same auction, so I'll select "Sample Online Auction".

Finally, select "Spa Heaven" from the list of items, and click "Copy Items".

That's it! You now have a copy of "Spa Heaven" in your auction. If you would like to watch a video on how to copy items click here.