Affiliated Computer Services has promoted a Lexington-based executive to chief operating officer of all commercial operations for the Fortune 500 company.

Tom Blodgett was executive vice president and group president of ACS Business Process Solutions. He will be one of two chief operating officers who are responsible for the day-to-day operations of the company.

ACS is the third-largest private employer in Lexington, with 2,000 workers, and the sixth-largest private employer in the state, with 4,000.