When Prime Minister Mulroney is deciding to call the next election, he will help make up his mind by reading a poll produced by a guy who wears an earring, dresses in casual chic and dabbles in rock 'n' roll. Allan Gregg (shown) is very much unTory, but he has propelled Decima Research into the top ranks of the polling industry. (CP PHOTO) 1988 (John Felstead)