There have been a number of articles written questioning whether Obama is actually an American citizen qualified to run for President. The issue has been fueled by the apparent refusal of the Obama campaign to make available a certified copy of his birth certificate. The closest they have come is to post a supposed copy on the web, which authenticity has been disputed by document experts and at least one employee of the Hawaii hospital records department where he claims to have been born.
This may or may not amount to something, but the MSM, of course, won't do any serious investigative work. A Pennsylvania Democratic Party affiliated attorney has filed suit to try to compel Obama to release his birth certificate, which he is resisting. This link to a YouTube video provides some information regarding the issues.