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.Some Republicans privately worry that his comments about Obama's birth certificate may have endeared him to the party's conservative wing that questions the legitimacy of Obama's presidency but also may have started to marginalize the Texas governor from the larger electorate. That could put the general election at risk should Perry win the GOP nomination.His comments certainly irked several GOP luminaries, like former Florida Gov. Jeb Bush, who in recent days have urged Republican presidential candidates to stop raising the issue. Others, like Mississippi Gov. Haley Barbour and campaign rival Jon Huntsman say it's bad for the GOP."If we take our eye off the ball called debt, if we take our eye off the ball called our position in the world — continue going with you know, two wars simultaneously — of course we can lose it," Utah's former governor said, speaking on ABC news' political webcast "Top Line" on Wednesday. "And if we kind of begin wasting time on the nonsensical and the silly issues like birtherism."Karl Rove, George W. Bush's political strategist, said Perry may be hurting his campaign. "You associate yourself with a nutty view like that, and you damage yourself," Rove said on Fox News.Perhaps for that reason, Perry seemed to try to put the issue to rest in an interview with two Florida news organizations, Bay News 9's "Political Connections" in Tampa and the St. Petersburg Times.Asked whether he had any doubt that Obama was an American citizen, Perry said: "I have no doubt about it." But he also suggested that raising the issue is "fun" and that people should "lighten up a little bit.""I don't think I was expressing doubts," Perry said of his comments in recent days that raised questions about Obama's birthplace. "I was having some fun with Donald Trump," the real estate mogul who this summer flirted with a presidential run and stoked the "birther" talk.Speculation about Obama's birthplace — a way to question whether his presidency is legitimate— has swirled among conservatives for years. As Trump fanned the issue earlier this year, Obama held a news conference to release his long-form birth certificate and try to put the issue to rest.While other Republican presidential candidates have kept their distance on the issue, Perry deeply waded into the topic in an interview published over the weekend in Parade magazine. He was quoted as saying that he has "no reason to believe" that Obama was not born in the United States. He also said he still wasn't sure if Obama's birth certificate is legit."I don't have a definitive answer," Perry said in that interview. And when it was suggested that Perry — and the world — had seen Obama's birth certificate, Perry said: "I don't know. Have I?"Then, in an interview with CNBC and The New York Times, Perry said the birth certificate question was "a good issue to keep alive.""It's fun to poke him a little bit," Perry said.And by Tuesday, Perry refused in South Carolina to answer a reporter's direct question about whether he believed Obama when he offered proof — in the form of a birth certificate — that he was born in Hawaii."I'll cut you off right there," Perry said when asked about Obama's birth certificate. "That is one of the biggest distractions that there is going. We need to be talking about jobs."Perry also offered to release his own birth certificate, saying: "If somebody wants to see my birth certificate, I'd be happy to show it to them," Perry said. "But the fact is that this is a distraction, and Americans really don't care about that, if you want to know the truth of the matter."