An embarrassing admission by John McCain that he does not know how many homes he owns triggered a furious back-and-forth with Barack Obama yesterday over which presidential candidate is more out of touch with ordinary Americans.

After weeks spent accusing Mr Obama of being a lightweight who is addicted to celebrity, Mr McCain — married to a multimillionaire beer heiress — was asked in an interview how many properties he owns.

“I think — I’ll have my staff get to you,” he struggled in reply. “It’s condominiums where — I’ll have them get to you.”

His campaign later said that he and his wife, Cindy, have at least four homes in three states, although it is believed the couple actually own seven.

With polls showing their race is tighter than ever, and with advisers urging him to push back harder against attacks by Mr McCain, Mr Obama seized on the remarks in appearances throughout the day. He also referred to a flippant comment his rival made recently that being rich in America meant earning at least $5 million (£2.7 million) a year.

Mrs McCain is estimated to be worth $100 million, based on the Arizona beer distribution network of her late father. The Obama campaign has been trying to publicise the wealth of his rival to counter criticism that he is a Harvard-educated, fussy elitist.

Mr Obama told a crowd in Virginia: “I guess if you think being rich means you’ve got to make $5 million and if you don’t know how many houses you have, it’s not surprising you might think the economy is fundamentally strong.”

He added: “But if you’re like me, and you’ve got one house . . . you might have a different perspective.”

The McCain campaign used the remarks to revive the issue of the Chicago home of Mr Obama, which was purchased with financial help from Antoin “Tony” Rezko, a former donor who was convicted on corruption charges in June. It also gave the Republican’s aides another chance to remind voters of Mr Obama’s cringe-making remarks to Iowa farmers last year when he decried the price of rocket salad in Whole Foods Market, an upscale grocery store not found in the Hawkeye state.

In a statement the McCain camp said: “Does a guy who made more than $4 million last year, just got back from vacation on a private beach in Hawaii and bought his own million-dollar mansion with the help of a convicted felon really want to get into a debate about houses? Does a guy who worries about the price of arugula \ and thinks regular people ‘cling’ to guns and religion in the face of economic hardship really want to have a debate about who’s in touch with regular Americans?”

The Obama campaign released an advertisement, Seven, mocking Mr McCain’s multiple property ownership.

Mr Obama, meanwhile, announced last night that he had chosen his running-mate, who is expected to be named within 48 hours. “I won’t comment on anything else until I introduce our running-mate to the world,” Mr Obama told USA Today.

Amid fevered speculation as to whom he will pick, Mr Obama dropped some hints in an interview with Time magazine the day after he had repeatedly referred to his choice as “he”. Asked what his choice would tell America about himself, he replied: “I try to surround myself with people who are about getting the job done, and who are not about ego, selfaggrandisement, getting their names in the press.”

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