Herein the electrochemical polymerizations of thieno[3,4-b]thiophene (T34bT) and 3,4-ethylenedioxythiophene (EDOT) and the electrochemical copolymerizations of T34bT and EDOT carried out in tetrabutylammonium perchlorate and tetrabutylammonium hexafluorophosphate electrolyte are compared utilizing cyclic voltammetry, chronocoulometry, and chronogravimetry. Simultaneous polymerization of T34bT and EDOT produced a copolymer, as confirmed by vis-NIR spectroscopy. The simultaneous polymerization of T34bT and EDOT exhibits a peak for monomer oxidation intermediate to the monomer oxidation peaks for each of the single component monomer systems. Furthermore, the copolymer exhibited tremendous stability to n-doping in comparison to either of the homopolymers of T34bT or EDOT. Polymerization rates as determined via chronogravimetry were found to be highest for EDOT with the lowest rate being obtained for the copolymerization of T34bT and EDOT. All polymers exhibited high anion dominancy (>80%) with the highest value, similar to92%, exhibited by PT34bT. Doping levels ranging from 27 to 38% were obtained for polymers containing T34bT. PEDOT was determined to exhibit doping levels of approximately 15%.