No, there is not a cotton with the loftiness of poly. Cotton is a low loft batting. Natural fiber with high loft would be wool. Hobbs and Quilters Dream both make a very nice washable wool batting but it is very spendy. I reserve wool for special quilts. Many show quilters use wool.
High quality polyester bats with loft: Hobb's Polydown, Quiltersdream Dream puff are two that I have used. I like both but the Hobbs polydown is easier to find for me and less expensive for me. Another thing I like to do a lot is to double up layers of batting. I will very often mix a layer of cotton or cotton blend with a layer of poly on top to give the quilting definition and poof factor. But I quilt with a Longarm. It is very heavy to manipulate a 2 layer batted quilt in a domestic sewing machine.
Connecting threads has batting on sale at 30% off a couple of times a year on Hobbs products with free shipping on orders over $50. Before I got my resale tax certificate I would stock up then. As they just had the sale last month they probably won't have it again for another month or two. Just watch their website or sign up to receive their catalog so you know when it is happening.
http://www.connectingthreads.com/Quilting.cfm