Obama is payback for Chester Alan Arthur (whose eligibility is also disputed).
Chester A. Arthur was born in 1829. The Fourteenth Amendment granted birthright citizenship to all those born in these United States, but it was passed in 1868. Obama was born in 1961. Once he produces the long form birth certificate with a U.S. birthplace on it, this is a dead issue. The argument that you must be the child of two U.S. citizen parents in order to claim natural born status is hogwash imo. Under that discredited argument, people like Bobby Jindal are ineligible to run for office.