No Kly, Labunski doesn't challenge Madison's title as the Father of the Constitution. In fact, he only devotes a handful of pages to describing the Convention and those are friendly to Madison (as is the whole book). Of course, I am of the opinion that without Madison as the protagonist there probably would never have been a Convention and thus no Constitution as we know it.

Yes, Labunski does write alot of words about those external political influences not only on the BOR, but on the Constitution's ratification journey. You mention his Congressional run for office and Labunski writes alot of words about that in particular. Also, he brings to life Patrick Henry's near obsession with defeating the Constitution's ratification and his equal obsession with getting the amendments suggested by Virginia to include structural changes to the Constitution.