Upon arriving in New York, AuCoin landed small roles in several soap operas, including Guiding Light and The City. In the early 2000s, AuCoin appeared in episodes of The Sopranos and the first of many episodes of Law & Order. has more recently had recurring roles in Netflix's House of Cards, The Americans, and the Showtime original series Billions. He has also appeared in other television series, such as Madam Secretary, the NBC miniseries The Slap, Unforgettable, Person of Interest, Forever, The Following, Elementary, The Good Wife, White Collar, Gossip Girl, Blue Bloods, among others. He played the regular recurring role of Peter Keatch in the CBS series Waterfront, which was canceled before ever airing, despite having shot five episodes.