A simple and ubiquitous nickel(II) complex NiCl2(PPh3)(2) catalyzes polymerization of oligothiophenes. Treatment of chlorobithiophene with chloromagnesium 2,2,6,6-tetramethyl-piperidin-1-yl lithium chloride salt (TMPMgCl center dot LiCl) followed by addition of 2.0 mol% NiCl2(PPh3)(2) undergoes deprotonative polymerization leading to poly(3-hexylthiophene) (P3HT) with M-n = 13000 and M-w/M-n = 1.67 (74% yield). The related terthiophene and quaterthiophene also polymerize to afford the corresponding polythiophene while little polymerization takes place with 2-chloro-3-hexylthiophene under similar conditions.