Embodiments of the invention include analyte-responsive compositions and electrochemical analyte sensors having a sensing layer that includes an analyte-responsive enzyme and a cationic polymer. The sensing layer can beneficially further comprise a redox mediator material that assists in transferring electrons between the enzyme and an electrode. The mediator can be associated either covalently or noncovalently with the cationic polymer, which, in turn, is disposed in close proximity to an electrode surface. Various organic ligand/transition metal complexes have been found to be useful in the role of the redox mediator. Also provided are systems and methods of making the sensors and using the electrochemical analyte sensors in analyte monitoring.