On the day of his State of the Union address, President Barack Obama walks from the Oval Office along the Colonnade of the White House in Washington, Tuesday, Jan. 24, 2012. (AP Photo/Haraz N. Ghanbari)
** FILE ** President Obama sits with White House Chief of Staff Bill Daley while meeting with the Council on Jobs and Competitiveness on Jan. 17, 2012, in the State Dining Room of the White House. (Associated Press)
President Obama, accompanied by leaders from the private sector and the government, speaks in the East Room of the White House in Washington on Wednesday, Jan. 11, 2012, to encourage companies to insource and invest in America. (AP Photo/Manuel Balce Ceneta)
President Barack Obama is presented with a Dallas Mavericks team basketball jersey from Dirk Nowitzki as he honored the 2011 NBA basketball champions Dallas Mavericks, Monday, Jan., 9, 2012, in the East Room of the White House in Washington. (AP Photo/Pablo Martinez Monsivais)
Former Massachusetts Gov. Mitt Romney (left) gets the endorsement of Sen. John McCain in his White House bid during a town-hall meeting in Manchester, N.H., on Wednesday, Jan. 4, 2012. (Rod Lamkey Jr./The Washington Times)
President William Howard Taft was the heaviest of American presidents and had a 54-inch waist, but he was elected in 1908 and subsequently installed an extra-large bathtub in the White House to little fanfare. More than a century later, can a heavy-set candidate win?
**FILE** Demonstrators outside the White House march in November with a replica of a pipeline during a protest of the planned Keystone XL pipeline that would bring tar sands oil from Canada to Texas. (Associated Press)
**FILE** Canadian Prime Minister Stephen Harper (left) listens as President Obama speaks following a meeting at the White House in Washington on Dec. 7, 2011. President Obama warned congressional Republicans that he would reject any effort to tie extraneous issues to an extension of the payroll tax cut, including the approval of an oil pipeline between the U.S. and Canada. (Associated Press/The Canadian Press)