that decision is. we know he's expected to watch the documentary and then be around for sort of a q&a session. i suspect that question will come up. how he will respond to that, we're going to be right here to let you know. >> leyla santiago, thank you so much. the democratic field is full of new faces, including two horror under 40, both hawaii congresswoman tulsi gabbard and south bend, indiana mayor pete buttigieg are 37 years old. if one of them wins, that would make them the youngest u.s. president in history. here's cnn's jeff zeleny. >> reporter: everywhere i go people are sometimes, especially here in iowa, a little too polite to ask the question of why a 37-year-old mayor thinks he has any business being in a discussion about the highest office in the land. >> reporter: that's precisely the question facing pete but ajudge, the youngest candidate in the presidential race. he's the mayor of south bend,