The prize for most iterations goes to 28-80mm (8 total):
7 non-L lenses in both USM and non-USM varieties (I, I USM, II, II USM, III USM, IV USM, V USM - all f/3.5-5.6)
1 L lens (28-80mm f/2.8-4L USM)
There are only 3 Canon 70-300mm lenses, but there are another 7 lenses that are 75-300mm.