Big OOOPS with aluminum cookie cutters...badly tarnished.?

I bought some adorable vintage aluminum cookie cutters just for fun. While I do like to use my cutters, I thought I'd be smart and just toss them into the dishwasher one day when I had a little extra space just to clean them up a little. They came out with ugly gray spots all over them and now I am sad that I may have ruined them. I didn't realize that the harsh dishwasher detergent and aluminum may not mix. Is there any way to remove this ugly, spotty tarnish?