With Hillary Clinton never seriously in the running, Joe Biden has always been the best option on Barack Obama's vice-presidential shortlist. True, the presence of this 35-year Senate veteran on the Democratic ticket undercuts Mr Obama's claim to be offering a fresh "non-Washington" approach to the country's problems. Nor does Mr Biden bring a trove of electoral college votes. His tiny home state of Delaware offers only three and, with or without him, was already a certainty for the Democrats.
But the pluses far outweigh the minuses. As chairman of the powerful Senate Foreign Relations Committee, Mr Biden offers the foreign policy heft Mr Obama lacks. The absence of that has been especially visible during the Russia/Georgia crisis – one reason for John McCain's comeback in the polls. But even if Georgia hadn't erupted, another global flashpoint would have done before the election, focusing attention on the Illinois senator's lack of experience. With Mr Biden he can fend off such criticism far more convincingly.
In other ways, too, the direct, outspoken – if sometimes garrulous – Mr Biden complements the more detached and cerebral Mr Obama. Mr Biden is not just a foreign policy specialist. He is a northeastern Catholic of populist bent who grew up in blue-collar Pennsylvania. As such he should help Mr Obama to connect with the white working-class voters in key swing states such as Pennsylvania, Ohio and Michigan who went for Hillary Clinton during the primaries, and may be sorely tempted by Mr McCain in the election.
Yes, Mr Biden has been prone to gaffes, which Republicans are sure to bring up against him. But in Congress, he has proved his ability to work with Republicans on specific issues. Mr Biden is popular on both sides of the aisle. If Mr Obama is serious about bridging the partisan divide in Washington, Mr Biden is as good a bet as anyone.
However, he – or whomever else Mr Obama might have chosen, even Hillary Clinton – can only do so much. This November, as always, Americans will be voting for president, not vice-president. Only once in modern times, when Lyndon Johnson helped John Kennedy to carry Texas in 1960, has a vice-presidential choice arguably changed the final result. In 1988, despite picking the much-mocked Dan Quayle as his running mate, George Bush Snr easily defeated Michael Dukakis and the impressive Lloyd Bentsen as his No 2.
The 2008 election is about Barack Obama. If Mr Obama can convince voters he is up to the job, and overcome doubts about his youth, his commitment and his race, then he will win. If he can't, he loses – with or without Joe Biden.
Joe Biden is important for what his choice reveals about Mr Obama himself. In this case, the message is encouraging. The candidate has acknowledged his areas of weakness, and picked the running mate best able to address them.
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