You can most definately sand them out and polish them. Start sanding the dry spray areas with a bout 1000 grit wet paper on a soft block. When it dries and you don't see any shiny spots in the dry spray sanded area move up to 1500 grit, and i even go finer like 2000. If you go 2000 you could hand polish it with a medium coarse compound and move up with a fine come from there. It's a little time consuming but the results will be to your liking. If you wish you could finish polishing with a final lite cut polish and glaze. This will be your preference.
Hope this helps.