LONDON, United Kingdom (AFP) — Anti-austerity socialist Jeremy Corbyn was trying to pick a shadow Cabinet yesterday after winning the leadership of Britain’s Labour Party, in a leftward shift that finishes its centrism under Tony Blair.

The veteran left-winger created a buzz of excitement with his clear-cut victory that marks a break with the legacy of controversial former Prime Minister Blair and his “New Labour” movement of the 1990s.

Corbyn — a 200/1 outsider at the start of the contest — was starting work yesterday on putting together a shadow Cabinet, though several senior Labour figures have ruled themselves out from serving under him.

However, Labour’s new deputy leader, Tom Watson, told BBC television there was “zero chance” of a successful coup against the new chief, saying moderates had to respect Corbyn’s “huge mandate”.

“He wants to build a broad-based party, he wants a front bench that represents all the talents and all the views,” said Watson, whose role involves overseeing party unity.

He said he hoped to persuade Corbyn of the merits of Britain staying within NATO and not going down the path of unilateral nuclear disarmament.

Senior Labour figures, including its previous leader Ed Miliband, have called for party unity, though he is among those who have ruled themselves out of serving on Labour’s frontbench.

Corbyn, a 66-year-old bearded vegetarian and a veteran of protest politics, won the Labour leadership with 59.5 per cent of the vote in a result that was hailed by the hard-left Syriza in Greece and Podemos in Spain.

“Death of New Labour,” read The Sunday Telegraph newspaper’s front-page headline.

“Labour isn’t dead, Blairism is, Jeremy Corbyn finally killed it,” the pro-Conservative weekly said, adding that Corbyn had defeated “boring Blairites”.

The Guardian’s columnist Rafael Behr said Blairism was “buried beneath the rubbleand a different structural and cultural divide has been revealed.

“It is between established Labour… and insurgent Labour, a complex hybrid of organised coup by dogged old warriors of the left and spontaneous, organic uprising by idealistic new recruits.”

Many commentators noted the vibrancy behind a Corbyn campaign that successfully harnessed the power of protest movements and social media.

Some 15,500 people have joined the Labour Party in the 24 hours since Corbyn’s election, general secretary Iain McNicol said, taking the membership to “325,000 and rising”.

“A genuine buzz and excitement has surrounded the election of a British political leader,” Dan Hodges wrote in the pro-Conservative Daily Telegraph, although he concluded the result would be “suicide”.

Corbyn was a dissenter against Blair’s “New Labour”, having rebelled against the party leadership more than 500 times since 1997.

Blair warned ahead of the leadership vote that Corbyn would be an “electoral disaster”.

A co-founder of the Stop the War anti-war movement, Corbyn advocates unilateral nuclear disarmament, ending austerity and increasing public spending.

In his first pronouncement on Corbyn’s election, Conservative Prime Minister David Cameron said Labour were dangerous for Britain.

“The Labour Party is now a threat to our national security, our economic security and your family’s security,” he said on his personal Twitter account.

Opinion polls predicted a hung Parliament, but in swathes of marginal seats, voters swung to the Conservatives, leaving pollsters stunned.

Cameron’s centre-right party won enough seats in May to form a slim majority government, taking 330 of the 650 seats to Labour’s 232.

Corbyn is expected to receive a hero’s welcome at the Trades Union Congress tomorrow, before facing Cameron in Parliament on Wednesday.