Vice President Joe Biden said on Thursday he is trying to determine whether he has the emotional energy to mount a White House bid in 2016 but cannot say yet whether he can do it. Biden, in Atlanta for a foreign policy address, was asked what his thinking was on a potential campaign for the Democratic nomination. 'The most relevant factor in my decision is whether my family and I have the emotional energy to run,' said Biden, who lost his son, Beau, to cancer earlier this year. 'I can't look you straight in the eye now and say I know I can do it.'