I don't think Clinton would ever have said it, at least publicly. Her campaign, however, was clearly implicated in surreptitiously spreading the rumors, which went viral in the winter of 2008-09, as Obama emerged as a serious threat to the planned Hillary coronation. Some of this was eventually tracked back to Sidney Blumenthal, but he surely wasn't alone. The birtherism stuff originated on the 'rat side of the aisle. It went viral when, and only because, Obama stonewalled. "Shut up, he explained" is not a good response to such questions.
I'm sure Clinton would disclaim any knowledge of this. Her denial will be persuasive to people who think she is trustworthy. I don't know any such people, but I understand that there are some out there somewhere.