Not sure. The nose does look like Vince Fosters, but I think those jowels and mouth look like Webbster Hubble's
Look at the mouth on Hillary in that picture....Chelsea could have gotten MOST of her mouth from her Mom...
I do see your point about Hubble though...and I know more people believe she is Hubble's, but on that on post with all three "Dads"...the shape of her nose is what caught my eye...but, I will defer to the masses.
Too bad we can't take a DNA test...