Ken Livingstone became tearful this week at the broadcast of his mayoral election video. Channel 4 News looks at some other notable public blubs.
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Politicians have often been known to shed a tear on occasion. Winston Churchill, a man in tune with his emotions (and plagued by what he called the "black dog"), was noted for the regularity of his teary interludes in parliament during the Second World War.
Through the decades, political leaders have demonstrated their softer side, crying at memorials and funerals, and during speeches about devastating events.
This week, however, we were reminded of another brand of blubbing - that related to more personal concerns. On Wednesday, London mayoral candidate Ken Livingstone openly cried as he watched his campaign video, broadcast at the unveiling of his manifesto.
Livingstone brought his hands to his eyes and rubbed away tears with his fists, as might a small child. Labour leader Ed Miliband gently comforted him with a pat on the back.
Was the campaign a tearjerker? It features a series of ordinary Londoners calling for a mayor "for the majority, not just a few" and imploring the Labour candidate: "Come on Ken, we know you can do it!"
Ken, clearly stirred by his supporters' sentiments, described the challenge of mayoral re-election as "a huge responsibility".
Perhaps the latest ComRes poll also had something to do with his welling up: Livingstone currently trails behind incumbent Boris Johnson by six percentage points.
Whether he will be rubbing away tears of regret or of joy on 4 May remains to be seen.
Margaret Thatcher left Number 10 Downing Street for the last time with tears in her eyes in 1990. It wasn't the first time the Iron Lady had turned a watery - in 1984 she cried during a speech at the Conservative Party conference, the day after the Provisional IRA bombed the Grand Hotel, where she and other politicians were staying. But in 1990 the tears were for herself.
In March this year, Russia's new president-elect Vladimir Putin showcased watery eyes as he addressed supporters during a rally in Manezhnaya Square in central Moscow (see picture, right). The tears contrasted with his usual cultivation of a strongman image.
Stateside, where the stiff upper lip does not prevail, sobbing is not quite so rare an occurrence. Hillary Clinton wept after losing the Iowa primary to Barack Obama in 2008.
This Wednesday was not Livingstone's first teary outing. In 2007 he apologised for London's role in the transatlantic slave trade and, again, demonstrated the two-fist eye rub.
And finally, a famous blub boast. Some politicians find it easier to talk about crying than to do it in public - Ed Balls has admitted to crying at the Antiques Roadshow.