Updated at 8:12 a.m. ET: It took a zip line to stop Boris Johnson laughing, even then it was only for a few minutes.

If every Olympic Games has a breakout star, London’s mayor is surely in contention along with Ryan Lochte and Ye Shiwen.

Johnson might not be an athlete but he would surely get gold for grabbing attention.  From mocking Republican presidential candidate Mitt Romney in front of a crowd of thousands to risqué comments about volleyball players, Boris Johnson has awarded himself a starring role during London 2012. While some see a larger-than-life personality, perfectly representing his city, others believe it is another big step in a marathon effort to become British prime minister.

That might sound ridiculous, but consider how far Boris has already come (Alexander Boris de Pfeffel Johnson only needs one name). He was a journalist who found wider attention appearing on satirical quiz shows. His persona is one of an upper-class buffoon, with a messy mop of blond hair and a ready response of ‘oh cripes’ to tricky situations. But his shambolic appearance masks a shrewd and focused politician. It’s a combination that has allowed him to defy the political odds:  winning two mayoral elections as a Conservative in a left-leaning city at a time when his party is unpopular.

PhotoBlog: Boris Johnson, London mayor, stuck on a zip line

Ask a London cabbie what he thinks and here’s the response: “He’s my type of politician,”said Michael Murphy. “He’s a big personality and that’s what you need in a city like London.”

Boris doesn’t scare the voters -- he entertains them. On the Late Show he laughed along as David Letterman mocked his hair and then said his own bike-hire scheme was “Communist.” As the Olympics began he described female beach volleyball players as glistening “like wet otters.” It’s far from his worst gaffe and yet they never seem to do him any harm. In fact, many believe they add to the mayor’s eccentric, “real” persona.

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Boris Johnson’s biographer describes it as the ability to relate to the man in the pub.

“He hears the central ridiculousness of political life and can see the comic side,” Andrew Gimson told NBC News. “People love that because most people are skeptical about politicians.”

Johnson’s fellow Conservatives are taking notice. A recent poll showednearly a third would like him to take control of the party if Prime Minister David Cameron were to step aside.

The perception of rivalry between the two is exacerbated by a shared history. Both went to the elite boarding school Eton College before studying at Oxford University.

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“He considers himself to be a great deal more able than David Cameron,” Gimson said. “He considers Cameron his warm-up act.”

It could be quite a while before Johnson takes the main stage.

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He would first need to be elected to Parliament, then elected leader of the Conservative Party. Yet it is something being taken seriously in London.

In the Daily Telegraph newspaper, Benedict Brogan sums it up: “Westminster is divided between those who now believe him to be unstoppable, and those who can’t stop laughing at the idea that he is being taken seriously as an alternative Prime Minister.” 

There was plenty of laughter as the mayor was rescued from the zip line on Wednesday, cheerfully waving union flags as he was pulled along. It’s an indicator of how powerful Brand Boris has become, that this seemed neither strange, nor likely to detract from his growing popularity.