Nightly News | October 26, 2011
BRIAN WILLIAMS, anchor: Now we turn to politics, the GOP campaign trail. And that sound you might have heard today, that would be candidates walking back their positions on some of the issues. After days of questions and ambiguous answers, first of all, Rick Perry told a Florida newspaper today he has no doubt President Obama is an American citizen . He was just having a little fun the other day, he says, when he raised doubts about Obama 's birth certificate. And Mitt Romney is also backtracking, saying he backs Ohio 's Republican governor's 110 percent on a controversial collective bargaining measure that is on the ballot this November. It was just yesterday in Ohio , when asked by NBC News , that Romney refused to say whether he supported the ballot measure in Ohio .