Typically 3 to 4. Maybe 1 or 2 more on the practice squad.
Defend the running backs of the oposing team. They also can block thier opponents.
Typically two, but it depends. Sometimes there are more.
North Carolina Tarheels
Typically 3 or 4 due to the high probability of an injury it's important to have depth at the position
Yes, the New Mexico Razor backs are a semi pro football team. They are the longest running team in New Mexico Semi pro football history.
Earl Campbell, Gary Brown, and Eddie George were the best running backs the Oilers ever had. Eddie George did play in Houston before the team moved away.
Tana Umaga is a backs coach at Toulon, or more formally RC Toulonnais.
Rob Valentino is a U.S. major league soccer player that wears the number 35. Rob Valentino is a team member on the Colorado Rapids soccer team.
That was Hall of Famer Charley Taylor who led the team with 402 rushing yards. Other running backs for the Redskins in 1965 were Dan Lewis, George Hughley, and Pervis Atkins.
Rose Bowl
I am pretty sure that it is Brady Quinn and one of the browns wide receivers.