Hillary Clinton cemented years of goodwill with gays in 2000, when she walked in New York's Pride Parade. ``Having the first lady march was enormously powerful,'' said Representative Barney Frank, one of two openly gay members of Congress, both of whom are backing Clinton. ``I've never seen such a strong emotional outpouring.'' Now some gay voters, who have been among Clinton's most stalwart supporters and helped her defeat Barack Obama in Democratic presidential primaries earlier this month, may be drifting toward the Illinois senator, according to political activists and campaign officials. ``Clinton probably is still a little bit ahead of...