WASHINGTON (AP) — Republican presidential candidate Rick Perry said Wednesday that he has "no doubt" that President Barack Obama is an American citizen, staking out a definitive position on the matter after spending several days stoking widely debunked claims that the Democrat was born overseas. Perry's comments come as he's struggling to right his troubled campaign, and as some Republicans question whether he's done irreparable damage to his run by dabbling in the so-called "birther" controversy in recent days.