Julian Zelizer: Ten Flubs that Helped Sink Candidates

Julian Zelizer is a professor of history and public affairs at Princeton University. He is the author of "Jimmy Carter" and the new book "Governing America."

Princeton, New Jersey (CNN) -- Late last week, the campaigns of President Obama and Mitt Romney released Web videos highlighting the mistakes their rivals have made on the campaign trail.

Obama's statement that "the private sector is doing fine" was the highlight for a Romney video, while one of the president's videos featured a remark by the former Massachusetts governor that the nation does not need more firefighters, teachers or police officers. We can expect the gaffe wars to continue, since they are a staple of presidential campaigns.

Even though such statements are far from a fair indication of a candidate's record or stance on the issues, and often they are accurate statements taken out of context, they can be devastating to a campaign.

Some off-kilter comments are too slight to sink a candidacy, but when they play into preconceptions of a candidate, the remarks -- and even sometimes a gesture or sound -- can be potent....