IT was just a printing error, but John McCain’s campaign team did not spell his name right in an advertisement last week – it was apparently paid for by “Johm” McCain.

Last week, while questioning General David Petraeus in Congress about progress in Iraq, the Arizona senator also garbled the distinction between the Sunni Muslims backing Al-Qaeda and the Shi’ite radicals who are sponsored by Iran.

Senator Joe Lieberman, his friend, had already had to whisper a correction in his ear last month when he claimed that Al-Qaeda was being trained by Iran. “I’m sorry; the Iranians are training the extremists, not Al-Qaeda. Not Al-Qaeda, I’m sorry,” McCain said hastily.

Republicans fear their 71-year-old candidate, who would be the oldest president to enter the White House if elected, is having too many “senior moments” on the campaign trail.

They recall how Bob Dole, who ran against Bill Clinton at the age of 73 in 1996, was made to look a duffer by his younger opponent.

Scott Reed, Dole’s campaign manager, said last week: “McCain’s age will be made an issue by folks, from the Democrats to late-night comics.”

The ribbing has already begun. David Letterman, the television chat show host, recently welcomed McCain on his show with a stream of jokes about his age. “He looks like the guy who always has wiry hair growing out of new places. He looks like the guy who points out the spots they missed at the car wash,” he said.

A new book, The Real McCain, concentrates on McCain’s reputation for ill-temper rather than his age. One Republican senator said the idea of President McCain sent “a cold chill down my spine” because he was “hot-headed” and “erratic” and allegedly shouted, “F*** you,” at a Republican senator in an immigration debate last year. McCain claims the book is full of errors.

McCain intends to hold a meeting of doctors next month to answer questions about his health and has promised to get on with selecting a vice-president: “I’m aware of the enhanced importance of this issue because of my age.”

Howard Dean, chairman of the Democratic National Committee, claimed last week that voters often mentioned McCain’s age and “old-fashioned” views in their focus groups. “We didn’t bring it up – they volunteered it,” he said, pretending the Democrats would not make his age an election issue – even though he just had.

McCain's senior moments

Video: McCain calls himself a proud liberal

Video: McCain talks about Al Qaeda training in Iran

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