Sen. Joe Biden of Delaware is Barack Obama's pick as vice presidential running mate, The Associated Press has learned.
Biden, 65, is a veteran of more than three decades in the Senate, and one of his party's leading experts on foreign policy, an area in which polls indicate Obama needs help in his race against Republican rival John McCain.
The official who spoke did so on condition of anonymity, saying they did not want to pre-empt a text-message announcement the Obama campaign promised for Saturday morning.
