* American Loupe holds one-stroke lead * Defending champion McIlroy six back * Blair disqualified in bizarre fashion (Updates to end of round) By Andrew Both CHARLOTTE, North Carolina, May 6 (Reuters) - Veteran Phil Mickelson used his short game magic to claw his way within three strokes of halfway leader Andrew Loupe after the second round of the Wells Fargo Championship at Quail Hollow on Friday. On a day when defending champion Rory McIlroy roared into contention before a bogey-bogey finish left him trailing by six, Mickelson hit only nine greens in regulation but used his vaunted touch around the greens to card a two-under-par 70. More...