The filmmaking is as conventional as documentaries get, and little revelatory footage is unearthed. Choir-preaching? Undeniably. But even if we weren't praying that its subject lives another 6 years, this would still be a prime example on how to organize a doc to make a historical narrative smooth and purposeful. And, even while it's busy being starstruck, it has a perceptive eye for shifting American political life.