A look back at VP Joe Biden's most memorable gaffes

(CBS News) Vice President Joe Biden's commented Tuesday at a campaign stop in Charlotte, N.C., that the middle class in America has been "buried" during the last four years. The remarks are now being critiqued by Republicans, who say that's an indictment of the Obama administration.

As Mitt Romney prepares for Wednesday night's first debate and tries to gain some traction against the president, he worked up a new line of attack with an assist from none other than the vice president. And it wasn't the first time Biden's foot-in-mouth propensity has caused him trouble and given ammunition to the other side.

Biden "buried middle class" gaffe under fire
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Biden accused Romney of planning to raise taxes on the middle class to pay for tax cuts for the wealthy, saying, "How they can justify raising taxes on a middle class that has been buried the last four years? How in Lord's name can they justify raising their taxes with these tax cuts?"

Republicans pounced, calling Biden's remark that the middle class has been buried for four years a "stunning admission." The Obama campaign called that a "desperate and out-of-context attack."

The vice president shrugs off his tendency to shoot from the hip. In May, he said, "No one has ever doubted I mean what I say. The problem is I sometimes say all that I mean."

Tuesday marked the third time since the spring that Biden has made comments that needed to be cleaned up. In August, Republicans and some Democrats were outraged when Biden made this reference to an audience of African-Americans: "He's going to once again let the big banks once again write the rules. Unchain Wall Street. They're going to put you all back in chains."

Then there was time in May when Biden forced the president's hand on the gay marriage issue, going on MSNBC's "Meet the Press" and endorsing same sex unions, before the president's planned announcement. Biden said at the time, "I am absolutely comfortable with the fact that men marrying men, women marrying women, and heterosexual men and women marrying another are entitled to the same exact rights, all the civil rights, all the civil liberties. And, quite frankly, I don't see much of a distinction beyond that."

It may just be coincidence, but Biden has done almost no national TV interviews since then. But in a little more than a week, there will be plenty of questions for Biden on the debate stage against Paul Ryan who is famous for his command of wonky budget details. Biden best bet may be to simply stick to the script.

Watch Bill Plante's full report above.