Democrats play the Clinton card to lift Obama campaign

Now the question is if Clinton will remind Americans how good were the 1990s with a Democrat in charge (EPA)

No one knows better than Barack Obama that you dance with Bill Clinton at your peril – big egos can squash even nimble toes.

He is nonetheless turning to the former President to give him much-needed lift when Democrats meet in Charlotte, North Carolina, in five weeks' time for their party convention. Mr Clinton, whose nickname "Bubba" is a reminder of his own roots in the South, will usurp the role that would normally be Vice President Joe Biden's and deliver the keynote speech in primetime on the penultimate night of the convention. In it, he will formally offer Mr Obama as the nominee.

That the party is giving him star billing is a surprise only in the context of the sometimes tricky Obama-Clinton relationship. Yet the reasons are clear. Perennially popular, Mr Clinton will raise TV ratings and will be a reminder that a Democrat was in charge in the buoyant 1990s when the deficit was a surplus. It will also allow the party to boast unity. Notably absent when the Republicans gather one week earlier in Tampa, Florida, will be George W Bush, who has an entirely less steady standing in the public eye.

"There isn't anybody on the planet who has a greater perspective, on not just the last four years, but the last two decades, than Bill Clinton," David Axelrod, senior aide to the Obama re-election effort, noted to The New York Times. "He can really articulate the choice that is before people."

The campaign will be looking for help from Mr Clinton on several fronts, above all in connecting with white, blue-collar voters, especially men, many of whom remained loyal to the party when he was in office, but who have conspicuously failed to line up behind Mr Obama.

His taking centre stage might also help Mr Obama cling on to North Carolina, which he won by the narrowest margin in 2008.

Mr Biden has not been nudged aside entirely. Officials say he has been scheduled to speak immediately before Mr Obama on the last – and hopefully climactic – night of the convention, which will by then have shifted outdoors to the Bank of American Stadium in downtown Charlotte. The rift that opened between the Clinton and Obama camps in 2008 was mostly healed when Hillary Clinton, after losing the nomination, agreed to become Secretary of State in the new administration.

But Mr Clinton has still been an occasional bother to Mr Obama, including in recent months when he publicly parted ways with him on ending tax cuts for the rich (he has since backtracked) and when he said flatly that Mitt Romney's record as a businessman and former Governor qualified him to be President.