OT: He took a chance that Denver would not score a touchdown, which under the NFL's modified sudden death system would have ended the game (IMO the NCAA system is superior.) He was counting on a field goal at worse, which would have allowed the Pats to go four downs every series towards a tying field goal or winning touchdown. As mentioned in the previous discussion, it's an advantage on par with receiving the ball first.
All that is needed to make a happy life is within yourself, in your way of thinking. -Marcus Aurelius