| Oberg | Louis | Monmouth City | tailor | rep | _ | from Sweden |
| O'Farrell | Reb.T. | Monmouth City | parish priest | _ | _ | from Ireland |
| Oliver | O.F. | Monmouth City | mechanic | rep | from New York | |
| Olsen | Matt | Monmouth City | laborer | _ | _ | from Sweden |
| Olsen | A. | Monmouth City | clerk | _ | Luth | born Illinois |
| Ovenstein | Jacob | Monmouth City | employee Weir Plow Works | dem | _ | from Germany |
| Owens | Ed | Monmouth City | laborer | dem | Cath | from Ireland |