The national Associated TV/Zogby International telephone poll of 1,011 voters surveyed July 31-Aug. 1 finds McCain (R-Arizona) leading 42 percent to 41 percent over Obama (D-Ill.), which represents a sudden turnaround from the Reuters/Zogby poll of July 7-9 that showed Obama ahead, 46 to 36 percent in a four-way race with Libertarian Bob Barr of Georgia and liberal independent Ralph Nader. McCain made big gains among some of Obama’s strongest demographic groups – young adults, women and independents… McCain gained 20 percent while Obama lost 16 percent among voters ages 18-29. Obama still leads that group, 49 percent 38. McCain closed 10 points on Obama among women, although Obama still leads by a 43 percent to 38 percent.