Presumptive Democratic presidential nominee Barack Obama introduced Sen. Joe Biden to the nation as his running mate Saturday, telling supporters that he is "a leader who is ready to step in and be president..."The McCain campaign quickly pounced Obama for introducing Biden as "the next president of the United States" before quickly correcting himself to say "vice president." "Barack Obama sounded as though he turned over the top spot on the ticket today to his new mentor, when he introduced Joe Biden as the next president," McCain spokesman Ben Porritt said. "The reality is that nothing has changed since Joe Biden first made his assessment that Barack Obama is not ready to lead. He wasn't ready then and he isn't ready now."
Biden, chairman of the Senate Foreign Relations Committee, brings decades of experience that could help counter GOP attacks on Obama's lack of experience in foreign policy.
Biden abandoned his own White House run after a poor showing in Iowa's first-in-the-nation caucuses. He also ran for the 1988 Democratic presidential nomination but dropped out after charges of plagiarism in a stump speech. Biden is serving out his sixth term, making him Delaware's longest-serving senator.