Bernie Sanders’ trip to Rome (there’s no airport in Vatican City, though there’s a heliport) was on a chartered Delta Boeing 767-332ER with 26 flat business class seats, 29 extra legroom economy seats, and 171 standard economy seats.
It’s worth noting that while Bernie Sanders charters from Delta, the Pope prefers American Airlines. While Papal infallibility only applies ex cathedra, promulgating official teachings of the Church, it’s interesting that his charter flight choices didn’t have persuasive power with the Bernie Sanders campaign. (In fact, Sanders has more in common with former Arkansas Governor Mike Huckabee who has earned Delta Diamond.)
Here’s the menu detail from the flight: