Biden adds experience and signals tough line

By John Whitesides, Political Correspondent - Analysis

DENVER (Reuters) - U.S. Democrat Barack Obama chose seasoned experience over a fresh face in making Joseph Biden his running mate on Saturday, hoping to broaden his appeal with a pragmatic selection that props up his biggest weaknesses and signals a tougher line against rival John McCain.

Biden adds foreign policy heft and a Washington insider's resume to a Democratic White House ticket headed by Obama, 47, a first-term Illinois senator dogged by questions about his readiness to be commander in chief.

Biden, 65, chairman of the Senate Foreign Relations Committee and one of the party's foreign policy heavyweights, could help answer criticisms from Republican McCain that Obama is too inexperienced to be trusted in the Oval Office.

The verbose six-term senator from Delaware also has a taste for political combat that some Democrats worry is lacking in Obama. The choice comes as Obama's campaign has turned up its attacks on McCain and polls show the November 4 election tightening.

"Obama recognized the gap on national security and he recognized the need to get tougher on McCain, and he chose the guy who can most quickly help him on both counts," said Democratic consultant Doug Schoen, a former pollster for President Bill Clinton.

Biden quickly went on the offensive at his first joint appearance with Obama in Springfield, Illinois, attacking McCain and repeatedly linking him to President George W. Bush.

"We cannot as a nation stand four more years of this," Biden said. "You can't change America when you supported George Bush's policies 95 percent of the time."

The choice also carries risks for Obama. Many Republicans -- and some Democrats -- wondered whether Biden would renew a long history of verbal gaffes.