FILE - In this Oct. 27, 1988 file photo, President Ronald Reagan, at podium, addresses supporters during an airport rally for presidential candidate, Vice President George H.W. Bush in Springfield, Mo. President Barack Obama flies Air Force One when he leaves town. So does Candidate Barack Obama. The distinction between the two roles for Obama matters because it helps determine who foots the bill for his travel. Either way, though, it's a safe bet that taxpayers are on the hook for at least part of the tab. Operating under the same rules that have governed presidential travel dating back to the Reagan years, Obama must reimburse the government for a portion of the costs associated with any political travel. But presidents of both parties have been secretive about the complicated mechanics. (AP Photo/James A. Finley, File)