Candidates making their case

— -- The marathon campaign for the White House nears its conclusion on Tuesday with voters poised to select the 44th president of the United States.

The winner will take office facing global economic instability and an array of foreign policy challenges.

Presidential nominees John McCain and Barack Obama sat down with USA TODAY reporters in separate interviews Thursday.

The candidates looked forward to how they would govern if elected and looked back at the contentious 21-month campaign that has brought them to this point.

Interviews by Kathy Kiely and David Jackson