A U.S. Marine stands at attention as Air Force One prepares to depart Andrews Air Force Base in Maryland on Wednesday, October 21.
Supporters of Republican presidential candidate Ben Carson stand in front his tour bus at a book signing in Edmond, Oklahoma, on Wednesday, October 21.
Hillary Clinton is reflected on a teleprompter during a campaign rally in Alexandria, Virginia, on Friday, October 23.
Democratic presidential candidate Martin O'Malley rolls up his sleeves Wednesday, October 21, as he arrives to host an event at the Microsoft Innovation & Policy Center in Washington.
Republican presidential candidate Jeb Bush speaks at a forum in North Las Vegas, Nevada, on Wednesday, October 21.
U.S. Secretary of State John Kerry poses with a guitar that was given to him by Spanish Foreign Minister Jose Manuel Garcia-Margallo during a meeting in Madrid on Sunday, October 18.
Republican presidential candidate Rick Santorum poses with a veteran during a forum in Plano, Texas, on Sunday, October 18.
President Obama shares a laugh with Agatha Sofia Alvarez-Bareiro, a high-school senior from New York, as he prepares to look at the moon during White House Astronomy Night on Monday, October 19. The event brought together students, teachers, astronomers, engineers, scientists and space enthusiasts for an evening of stargazing.