Afghan President Hamid Karzai's main election challenger said Sunday that he will withdraw from a planned Nov. 7 runoff, casting new doubts on the legitimacy of the Afghan government as the Obama administration debates U.S. strategy in the region.

A probe into fraud allegations in Afghanistan's presidential election carries important implications for the Obama administration's deliberations into war strategy there. Karen DeYoung of The Washington Post assesses the possible consequences with Judy Woodruff.