L.R.
Even if it's not a "dry clean only" bedspread, take it to a dry cleaner and ask if they can handle it. They have seen everything and dealt with everything. Unfortunately I suspect that your bedspread may be finished, since nail polish is very, very difficult to remove, even if a professional is doing it. If the dry cleaner can't do it, I'd get a new bedspread and lock up the nail polish. Good luck.
Updated
Even if it's not a "dry clean only" bedspread, take it to a dry cleaner and ask if they can handle it. They have seen everything and dealt with everything. Unfortunately I suspect that your bedspread may be finished, since nail polish is very, very difficult to remove, even if a professional is doing it. If the dry cleaner can't do it, I'd get a new bedspread and lock up the nail polish. Good luck.