Abstract: Water soluble light harvesting multichromophores having a plurality of pendant chromophore groups are provided. Water soluble light harvesting multichromophores according to certain embodiments are polymers that include a polymeric backbone having norbornene repeat units, a pendant water solubilizing group component and a pendant chromophore component. Polymeric tandem dyes based on the subject multichromophores are also provided that further include an acceptor fluorophore linked to a norbornene repeat unit of the polymeric backbone and configured in energy-receiving proximity to at least one pendant donor chromophore group of the light harvesting multichromophore. Also provided are labelled specific binding members that include the subject polymeric tandem dyes. Methods of evaluating a sample for the presence of a target analyte and methods of labelling a target molecule in which the subject polymeric tandem dyes find use are also provided.