A new, processible conducting polymer, poly[3-(4-octylphenyl)thiophene] has been chemically synthesized in chloroform using FeCl3 as the oxidant/reagent. The polymer, which is soluble in organic solvents such as chloroform, has been characterized using optical, electrical, and electrochemical methods. We observed a suppressed thermochromism and thermal undoping in this polymer compared to the case of poly(3-alkylthiophene) due to the separation effect of the benzene rings between the poly(thiophene) main chain and the flexible alkyl side chains. At low doping levels, polarons are found to be the charge carriers.