Hate to be the "Wet Blanket" guy here but oh well. Be very careful if you are using an electric blanket. I can tell you it really sucks to wakeup with one on fire because it shorted out!!!
For Momma and I we will just use body heat or a warmer pillow. Our daughter made us these "rice pillows" for those cold nights. It is a flannel bag she made and filled with minute rice. 3 minutes and your feet will be toasty for about an hour.
Sorry for going off topic but just wanted to warn people about the dangers of electric blankets. In our case a 15 minute fire ended up causing over $90K in damages. It was a blessing no one was seriously injured. Others haven't been so lucky. Good luck, John