AP
Democratic presidential candidate Senator Barack Obama walks with vice presidential candidate Senator Joe Biden at a rally in front of the Old State Capitol in Springfield, Illinois.

SPRINGFIELD, Illinois (AP):

Barack Obama introduced Senator Joe Biden of Delaware as his Democratic running mate yesterday before a cheering crowd of thousands, hailing him as a "leader who is ready to step in and be president".

Within minutes, Biden went on the attack against Republican presidential candidate John McCain, saying he would have to "figure out which of the kitchen tables to sit at" when considering his own economic future. It was a reference to McCain's recent inartful admission that he was not sure how many homes he owned.

Sound judgement

Before a vast crowd spilling out from the front of the Old State Capitol, Obama said Biden was "what many others pretend to be - a statesman with sound judgment who doesn't have to hide behind bluster to keep America strong".

Democrats coalesced quickly around Obama's selection of the 65-year-old veteran of three decades in the Senate - a choice meant to provide foreign policy heft to the party's ticket for the fall campaign against McCain and the Republicans.

Obama made a symbolic choice for the ticket's first joint appearance. It was a brutally cold winter day nearly 20 months ago when he stood outside the historic structure in the Illinois capital to launch his quest for the White House.

He returned in sunshine, the party's improbable nominee-in-waiting, a 47-year-old black man who outdistanced a crowded field of far better-known and more experienced rivals. Thousands of newly printed signs bearing the words Obama/Biden sprouted in the crowd that waited in anticipation in 90-degree (32-degree Celsius) temperatures.

Obama's remarks were carefully crafted to emphasise Biden's accomplishments in the Senate, his blue-collar roots and - above all - his experience in foreign policy.

Obama recounted the personal tragedy that struck Biden more than 30 years ago, within days of his election to the Senate, when his first wife and their child were killed in an automobile accident.

He said Biden raised his surviving children as a single parent, commuting between the Capitol and Delaware daily on the train.

"For decades, he has brought change to Washington, but Washington hasn't changed him," Obama said, attempting to blunt an emerging Republican line of attack that notes Biden's 30 years in the polished corridors of the Capitol."