It was the second consecutive year that Ruddy, Thomas and Madison served as captains.
"These are the guy they have confidence in," said Coach Dave Wannstedt. "They feel they've shown the leadership qualities that they want to represent this football team."
Wannstedt started a tradition last year of having players vote for permanent captains during the bye week.
Thomas' role as a leader became apparent after last Sunday's loss to the Jets when he was very critical of the team's effort.
"Even if I wasn't a captain, I was going to lead," Thomas said. "I don't see it as something I tell myself I have to do. It's something that just comes natural. It is an honor when the guys vote for you. there's got to be more than me and Sam. We need everybody to be a captain on this team. All 11 starters should be a captain."