Britain's Jeremy Corbyn offers a socialist alternative. Is anyone buying it?

The weekend election of socialist firebrand Jeremy Corbyn to lead Britain's Labour Party underscores a broader trend in Europe: left-leaning voters are looking for more leftism from their politicians. And while a chorus of critics here were quick to scorn Labour’s choice as political suicide, his supporters say it’s about center-left parties offering a real alternative to mainstream politics.

Among them is Ian McPherson, a media consultant and Londoner who says he stopped voting Labour in 2003 after former Prime Minister Tony Blair joined the US-led invasion of Iraq.

"This is almost a sanitation of daily politics, we are going to a new realm of more honest, clean politics in the benefit of the people,’’ he says. "It is good to finally have a real voice with real power in Parliament."

Mr. Corbyn’s is the latest strike by radical outsiders aiming at Europe’s political establishment. From Greece’s Syriza to Podemos in Spain, the radical left has begun to outflank mainstream left-wing parties, with mixed results at the polls. This applies squarely to Corbyn, who takes over leadership of an enfeebled opposition party that suffered its worst election defeat this year since 1987. 

Analysts say the question is whether Corbyn, a former union leader who favors the nationalization of rail companies and an end to Britain’s nuclear weapons, will become a credible leader or just cost more votes for his party.

"Lots of people who voted for him don’t really care that he is unelectable," says Helen Thompson, a politics lecturer at the University of Cambridge. “What Corbyn captures is something wider and more pervasive, which is the backlash against the professionalized political class. There was a sense that most Labour candidates were not eligible, then why not throw the weight behind opposition politics?”

Until recently, Corbyn was a largely unknown member of Labour’s rank and file. When he declared his candidacy in June he was seen as an also-ran. But his virulent anti-corporation and pacifist rhetoric mobilized a tide of new party members that overcame resistance from establishment Labour officials.

In an echo of Bernie Sanders’ surge among Democrats, his principles-first and emotional speeches came to inspire a generation of Britons tired of austerity and the unequal distribution of new wealth.

From socialist to socialist-lite

By background and ideology, Corbyn harks back to an earlier generation of Labour leaders. In the 1990s, after suffering successive election defeats to Margaret Thatcher’s Conservative party, Mr. Blair successfully led Labour to the center of the political spectrum. While the shift to a socialist-lite agenda paid off, luring more middle-class voters, the party struggled in this year’s election to offer a credible alternative to Prime Minister David Cameron’s center-right government.

Corbyn won by a landslide 60 percent, more than three times the support obtained by the runner-up candidate. He was helped by a surge in new members ahead of the vote, including 15,500 who joined over a single 24-hour period. It costs less than $5 to become a "registered supporter" of the party. 

Even Britain’s left-leaning media outlets remain skeptical of Labour’s new line-up. The Observer on Sunday wrote that “voters will resoundingly reject Corbynism in its current form.” Both Blair and his successor, former Prime Minister Gordon Brown, have depicted Corbyn as unelectable.

The new leader’s immediate struggle will be to unite his own party. Seven Labour lawmakers gave up their shadow cabinet positions following Corbyn’s election. He has already appointed their replacements, including his campaign manager John McDonnell, an outspoken critic of free-market capitalism, as shadow chancellor.

The British public will get a close-up look at Corbyn on Wednesday when he faces Mr. Cameron in the House of Commons during the weekly questions to the prime minister.

Corbyn’s pacifism and orthodox left-wing stand has drawn comparison to two historical Labour leaders. George Lansbury, the reformer who fought for women's rights and social justice, took over the party in 1932 with a vision of a socialist state. His efforts towards pacifism and de-militarization would prove ill-judged as Nazism and fascism advanced in Europe.

Michael Foot, leader in the early 1980s, was an ardent supporter of nuclear disarmament and of exit from the European Economic Community. In the 1983 general election, he suffered Labour’s worst showing since 1918.