Yes - I never have mine handy when I call, and it's never been a problem. They'll ask you for your name, address, last 4 digits of your Social Security, phone number, size shoe you wore in the fifth grade, number of times you've wanted to eat fast food but forced yourself to go home and cook instead, amount of money you saved by buying DVC, amount of money you spent on subsequent trips to Orlando, number of times you wondered why Mickey and Minnie aren't married, and number of times you secretly fantasized about being Cinderella, but eventually they will give you the number and make the reservation...
Just kidding, they just ask the basics!!!!! Hope you get your ressie!!!