Joe the plumber confronted Barack Obama on a walkabout in Toledo, Ohio, asking awkward questions about his plan to increase income tax on high earners. "I'm getting ready to buy a company that makes $250,000 to $280,000 a year," he said. "Your new tax plan is going to tax me more, isn't it?" John McCain seized on this - and on Mr Obama's reply, that "when you spread the wealth around, it's good for everybody". He mentioned Joe Wurzelbacher the plumber more than 20 times in the final presidential debate.
More Joes, championed by some young McCain supporters
It later turned out that Joe's real name was Samuel, he was not a licensed plumber, he was unlikely to be buying a company any time soon, and would probably benefit from Mr Obama's tax plans. He also refused to confirm that he would be voting for Mr McCain.
The original Joe, or Samuel, has spawned a number of others. Mr Obama's running mate, Joe Biden, said on the Tonight Show with Jay Leno on Thursday that in his neighbourhood they didn't know many plumbers making $250,000 a year, and that people were "kind of worried about Joe the fireman, Joe the policeman, Joe the real plumber with a licence".
This weekend the Democratic Party went a step further, running a pro-Obama telephone ("robocall") advertisement recorded by "Joe Martinez... a plumber from Denver, Colorado, calling for Barack Obama's campaign for change".
Joe Six-Pack is a close relative of Regular Joe, Average Joe, Ordinary Joe, Joe Schmo, Joe Blow and others. The name "Six-Pack" refers to his favourite drink rather than a well-sculpted washboard stomach.
The phrase "six-pack" in Joe's name does not refer to a muscular stomach
Republican vice-presidential candidate Sarah Palin sees something of Joe Six-Pack in herself. As she told one interviewer: "It's time that normal Joe Six-Pack American is finally represented in the position of vice-presidency… it's motivation for John McCain and I to work that much harder to make sure that our ticket is victorious, and we put government back on the side of the people, of Joe Six-Pack like me."
So Joe Six-Pack is definitely not a Washington insider. Nor is he responsible for the problems on Wall Street. He is a male version of the hockey mom. This is how Mrs Palin put it in the vice-presidential debate on 2 October, answering a question about the financial crisis: "One thing that Americans do at this time, also, though, is let's commit ourselves, just everyday American people, Joe Six-Pack, hockey moms across the nation, I think we need to band together and say, 'Never again, never will we be exploited and taken advantage of again by those who are managing our money and loaning us these dollars.'"
The Palins may be a bit wealthier than some Joe Six-Packs and hockey moms.
The Anchorage Daily News writes: "Add up the couple's 2007 income and the estimated value of their property and investments and they appear to be worth at least $1.2 million."
Joe Biden, Barack Obama's vice-presidential candidate, is the most prominent Joe on the Democratic side of the race. John McCain, a four-term senator, has referred to him as "Joe the six-term senator", but conservative columnists and bloggers prefer the derisive "Lunch-pail Joe Biden" - a reference to his habit of talking up his working class roots in the coal-mining town of Scranton, Pennsylvania (where most working men would have taken their lunch to work in a lunch box, or lunch pail).
Joe Biden in Scranton: He's been called "Pennsylvania's third senator"
One of the main reasons Barack Obama chose Joe Biden as his running mate - apart from his experience in foreign policy - was his potential appeal to working class white male voters. "The pick works if it is positioned as Obama picking a lunch-pail Dunkin' Donuts Democrat to complement his Starbucks Democrat brand," Democratic strategist Chris Lehane told the New York Times. But Mr Biden's grandfather was a mining engineer rather than a miner, and Joe left Scranton at the age of 10, when his father got a job at a car-dealership in Delaware.
It was this lunch-pail tendency that led him during his bid for the 1988 Democratic nomination to recycle parts of a speech by British Labour Party leader Neil Kinnock, asking why it was that he was the first Biden (Kinnock) in a thousand generations to go to college.
One of the least wealthy members of the Senate, Joe Biden nonetheless lives in a colonial-style lake-front house worth in the region of $3m.
Joe Lieberman, an Independent (formerly Democratic) senator from Connecticut, has been tipped as a possible Secretary of Defense or Secretary of State if John McCain wins the White House. Both are foreign policy hawks. Mr Lieberman endorsed Mr McCain in a speech at the Republican convention, and has appeared at countless McCain rallies around the US - he knows the routine, having been Al Gore's running mate on the Democratic presidential ticket in 2000.
Joe Lieberman: A tireless campaigner for John McCain in Florida
On the stump last week in Florida, he could not help joining in the fun surrounding another Joe: "Which of the two candidates is the fighter we need for Joe the Plumber?" he said. "I think you know what I'm saying, John McCain will fight for Jose el Plomero!"
If Mr McCain does not win the White House, Mr Lieberman's role in the Senate could be an interesting one. Since the 2006 mid-term elections, he has continued to caucus with the Democrats in the Senate, giving them a majority of one.
After the election, if the Democrats end up with 59 Senate seats, it will be in his power to grant them a filibuster-proof "super-majority" of 60.
Shoeless Joe has only played a bit-part in this election - alluded to by Sarah Palin, knowingly or not, in the vice-presidential debate with Joe Biden.
This is how it happened. Joe Biden launched into lunch-pail mode for one of his attempts to draw parallels between the McCain/Palin ticket and George Bush: "Look, all you have to do is go down Union Street with me in Wilmington or go to Katie's Restaurant or walk into Home Depot with me where I spend a lot of time and you ask anybody in there whether or not the economic and foreign policy of this administration has made them better off in the last eight years."
Sarah Palin turns on folksy charm
Sarah Palin replied: "I'll say it ain't so, Joe, there you go again, pointing backwards again. You prefaced your whole comment with 'the Bush administration'. Now doggone it, let's look ahead and tell Americans what we have to plan to do for them in the future."
The words "Say it ain't so, Joe" date back to 1920. They were allegedly spoken to Chicago White Sox baseball star Shoeless Joe Jackson by a broken-hearted young supporter, as Joe was leaving a grand jury hearing where he had admitted taking part in a match-fixing scandal.
(Chat show host David Letterman has suggested Mrs Palin set-up her use of the "Say it ain't so" quotation by asking Mr Biden before the debate if she could call him Joe.
Mr Biden's critics, meanwhile, have cast doubt on the suggestion that he spends a lot of time in Home Depot - and point out that Katie's Restaurant closed down a decade ago or more.)
Some of the Sarah Palin dolls - and reaction to them
You can buy GI Joe-style action figures of Barack Obama, John McCain and Sarah Palin. But the real GI Joes are the sons of the candidates who are, or have been, serving in Iraq.
Captain Beau Biden (real name Joseph Robinette Biden III, in other words, a genuine GI Joe) introduced his father at the Democratic Convention in Denver, with an oblique reference to his forthcoming deployment: "But because of other duties, it won't be possible for me to be here this fall to stand by him the way he stood by me. So I have something to ask of you. Be there for my dad like he was for me." His father responded: "Beau, I love you. I am so proud of you." Two days later, Mr McCain picked Mrs Palin as his running mate. She gave the Republican Convention the news that her son, Private First Class Track Palin, would, on 11 September, "deploy to Iraq with the Army Infantry in the service of his country".
Both VP candidates made speeches at their sons' deployment ceremonies. John McCain, by contrast, has maintained an almost total silence about his own son Jimmy's role in Iraq - a marine who returned from a tour of duty in February. Another of Mr McCain's sons, Jack, aged 21, is to graduate from the Naval Academy in 2009. This gives rise to the possibility of Mr McCain becoming the first occupant of the White House since Eisenhower to have a son at war.
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