Hubble Space Telescope Observations of Candidate Young Globular Clusters and Stellar Associations in the Recent Merger Remnant NGC 3921

New, high-resolution images of NGC 3921 obtained with the Wide Field and Planetary Camera 2 of the refurbished HST are presented. NGC 3921 is the remnant of two merged disk galaxies and thought to be a 0. 7+/-0. 3 Gyr old protoelliptical. A search for star clusters has yielded 102 candidate globular clusters (GC) and 49 separate, more extended stellar associations (A) brighter than V = 26. 0, the estimated completeness limit (corresponding to MV_ = - 8. 5 for H₀_ = 75 km s^-1^ Mpc^-1^). Most of these objects are newly discovered. Among the best-observed objects [V 40% during the merger, from about 270+/-60 GCs before to ~> 380 GCs after the merger. The inferred specific GC frequency is SN_ >~ 0. 7 at present and will, barring further mergers or significant cluster destruction, increase to SN_ >~ 1. 4, 1. 8, and 2. 9 over the next 2, 5, and 15 Gyr as the galaxy fades. Hence, within <~7 Gyr NGC 3921 may begin to appear as a normal elliptical with a GC population typical for Es in low-density environments.