I wondered the same thing. In fact my first reaction was to post that I thought that since John T. and James F. Denton (Guy V's Grandfather) were both from Bath County, Kentucky, then they probably were but that I'd need to research it, then I remembered that I have GEDCOM of Dentons going back to the 1500s.
I found them both and used PAF to do a quick relationship calculator and VOILA.
John T. DENTON and James F. DENTON are 1st cousins. Their common ancestors are William DENTON and Mary "Polly" HUNT.
This was amazingly simple to verify. Here is the link to the Denton Genealogy Website
http://www.dentongenealogy.org/I think the folks at the Denton Genealogy will be excited to have another "famous" Denton to add to the list.