If the New Jersey Nets select Marcus Camby from the University of Massachusetts in Wednesday's NBA draft, credit a promotional telephone poll among fans. Coach John Calipari's recorded voice was used to poll thousands of fans on draft selections, as well as opinions on free agents, current personnel and type of offense preferred. No. 2 draft favorite was Alan Iverson of Georgetown at 22%. The opinion poll was conducted by Bullet-Poll, Verona, N.J.; the cost was underwritten by TotalTel, Clifton, the long-distance carrier of the Nets.