AMSTERDAM, Sept 13 (Reuters) - Two radical groups from the political extremes suffered stinging defeats as the Dutch voted tactically for pro-European mainstream parties and political leaders seen as the best able to handle the euro zone crisis.
The hard-left Socialist Party and Geert Wilders' anti-immigration, anti-euro Freedom Party both fared far worse than expected in Wednesday's general election, a sign that the influence of some of Europe's populist parties, fuelled by the crisis and rising unemployment, may have peaked.
"This really shows voters were voting strategically. They realised the extremes are not the solution at the moment. The Dutch are not anti-European. They are pro-European," said Famke Krumbmueller of the Eurasia political risk consultancy.
Just a month ago, the former Maoist Socialists of Emile Roemer, who oppose austerity and bailouts for weaker euro zone countries, were either leading in opinion polls or neck and neck with Prime Minister Mark Rutte's Liberals.
Wilders' Freedom Party was snapping at their heels, having switched themes from his signature anti-Islamic immigration bashing to calling for the Netherlands to scrap the euro, bring back the guilder and leave the European Union.
The bleached-blonde Wilders suffered the biggest debacle, losing more than a third of his seats to tie for a distant third place with the Socialists, who held on to their 15 lawmakers.
Wilders' supporters either voted tactically, mostly for Rutte's Liberals, or deserted him in dismay at his ill-conceived strategy of bringing down a centre-right government and fighting the election on economics rather than immigration.
As the third-largest party in parliament since 2010, the Freedom Party had real influence on policy by keeping a minority Liberal-Christian Democrat coalition in office. Many supporters were upset when Wilders toppled the government in April by refusing to back budget cuts.
Several Freedom Party lawmakers quit in the run-up to the election, bringing internal conflicts and complaints about Wilders' alleged dictatorial style into the open.
Results from strongholds such as Wilders' home town of Venlo showed that voters had switched to Rutte's Liberals.
A survey by polling agency Ipsos Synovate found that 43 percent of former Freedom Party voters chose a different party because they felt it made no sense to vote for a group which others had ruled out as a coalition partner.
More than a quarter of voters said they voted tactically and 12 percent only made up their minds on election day.
"I voted for (Wilders) last time because of his social policy," said Benjamin, 24, an shoe shop assistant, who said he had switched to the Liberals.
"I expected him to do more for poor people. Ahead of this election, Wilders was very anti-euro and anti-Islam and I didn't like that."
Roos, an Amsterdam shop owner who like Benjamin declined to give her surname, said she had voted for Wilders in 2010 as a protest vote, but no longer supported him.
Ivo, a banker, said Wilders was "useful" in the political debate because he said things other politicians dared not voice about immigration and Islam.
Ever the master of the sound bite, Wilders conceded that his party had done badly, but vowed to keep fighting.
"My aim is to protect the Netherlands from the euro, immigration and the super-state," he told supporters on election night. "I will not quit."
He delivered some of the most powerful one-liners in the campaign, telling Rutte on television: "You talk about jobs, jobs, jobs but all I see are Poles, Poles, Poles."
But Rutte shot back: "You left the Liberals, you left the Catshuis (Prime Minister's office), and now you want to leave the euro. I wonder if you'll make it to the end of this debate."
The prime minister has had the last laugh.
Support for the Socialists had more than doubled since the 2010 election on the back of widespread resentment over austerity measures at home and the need to stump up billions of euros to lend to Greece, Portugal and Ireland.
But those gains evaporated as election day neared, largely because party leader Roemer, a former school teacher, performed dismally in one televised election debate after another.
Labour leader Diederik "Samsom was much more convincing in the election campaign than the SP leader," said Michael Riman, a 50-year-old conflict mediator who voted for the social-liberal D66 party.
Marijke Jongbloed, a documentary maker, said she switched allegiance from the Socialist Party to the pro-European Labour Party after Samsom impressed viewers in the debates with his authoritative style and knowledge of the issues.
"I do support SP (the Socialist Party) but for premier I would vote for Diederik Samsom, he's more cosmopolitan and more on the ball, and these days you have to mix and mingle with European leaders, schmoozing them, and I think Samsom is a little bit more savvy in this respect," Jongbloed said.
Roemer rattled investors by saying if he won the Netherlands would refuse to pay a European Union fine if its budget deficit exceeded 3 percent of GDP, breaking EU rules.
"Over my dead body," he told Het Financieele Dagblad.
Finance Minister Jan Kees de Jager said investors had called the ministry to seek clarity on Roemer's comments and he had to reassure them that the Netherlands would meet its obligations.
Former Socialist leader Jan Marijnissen said at the time Roemer's remark was a mistake but nothing to worry about. On Thursday, Marijnissen said the party would evaluate the election result "because something has clearly gone wrong".