By Chris Cottrell
BERLIN (Reuters) - Shrinking support for the Pirates, an upstart German party whose shock success in four state elections thrust it into the national limelight, could hurt Chancellor Angela Merkel's re-election chances next year, recent opinion polls show.
Voters initially attracted by the party's anti-establishment aura are being put off by its foggy stance on major issues and are drifting back to left-leaning parties.
If the Pirates fall below the five percent threshold needed to win seats in next year's parliamentary elections, it could become easier for center-left parties to defeat Merkel's center-right coalition.
The Pirates, whose core issue is to push for broader Internet freedom, would win 7 percent of the national vote if an election were held now, down from their peak of 12 percent in April, according to a poll this week by the Emnid Institute.
A poll by the Allensbach Institute measured a spring-to-summer decline from 10 to 6.5 percent while rival pollsters Forsa registered a slide for the Pirates from 13 to 9 percent.
"It was obvious that we were going to experience a drop in popularity after the unbelievable media hype after the Berlin election," said Pirates leader Bernd Schloemer, referring to the party's shock 8.5 percent score in the September 2011 city election.
The Pirates are not worried by growing doubts in the media about their skimpy program, Schloemer, 41, told Reuters. "The Pirates aren't going to let themselves be bullied by the media," he said.
The party captured Germany's attention with the improbable victory in Berlin and in three subsequent state elections, winning more than five percent and seats in the state assemblies of Saarland, Schleswig-Holstein and North Rhine-Westphalia.
Its surging popularity threatened to change the national political landscape as well. It was drawing more voters from the center left than the center right and Merkel's camp realized the Pirates' strength would actually raise her chances of winning the 2013 election.
One Merkel adviser told Reuters earlier this year that a collapse of support for the Pirates was one of the biggest worries for the Chancellor's Christian Democrats (CDU).
The polls show that may be happening now.
"If the Pirates remain an ad hoc protest movement, they'll be more of a flash in the pan like 'ATTAC' and 'Occupy' did but then be quickly forgotten," said Ulrich von Alemann, a political scientist at Duesseldorf University, referring to protest movements in recent years.
Germany has seen other ephemeral parties in recent decades. The "STATT Partei" (Instead Party) in Hamburg formed a coalition with the Social Democrats (SPD) to rule the city-state of Hamburg after winning 5.6 percent of a regional vote in 1993, only to disappear at the next election.
Similarly, a party led by an arch conservative judge named Ronald Schill surged to 19 percent in Hamburg in 2001 and formed a center-right coalition with the Christian Democrats. It hoped to become a national party but soon collapsed and disappeared.
Schloemer and Martin Delius, a Pirates' leader in the Berlin state assembly, said they knew the Pirates would not have an easy ride. They hope to iron out details of a comprehensive party platform at a national party congress in November.
"We might lose some old supporters, but they'll be replaced by new ones," Delius told Reuters. "It's a natural process."
Political scientists see problems for the party when other parties and the media press them on issues where they have little or no experience, such as Germany's role in solving the euro zone's sovereign debt crisis.
"The Pirates have until now only been regarded as a party that steals others' majorities," said Gero Neugebauer, a political scientist at Berlin's Free University.
Von Alemann at Duesseldorf University said that before the Pirates emerged, the center-left SPD and Greens enjoyed a lead in most polls over Merkel's center-right coalition. "But since the Pirates showed up, that's over," he said.
(Reporting By Chris Cottrell, editing by Tim Pearce)
(This story has been refiled to fix a spelling error in the second paragraph)