|Some analysts have suggested that state defeat could weaken Merkel's grip on her party [Reuters]
Germany's anti-nuclear Greens have defeated chancellor Angela Merkel's conservative Christian Democrat party in Baden-Wuerttemberg, following fears over the crisis unfolding in Japan.
Sunday's election saw the environmental party win a record 24 per cent of the vote, and is likely to see them lead a centre-left alliance in the state with the Social Democrats, who took around 23 per cent of the vote, according to preliminary results.
Winfried Kretschmann, the 62-year-old Green candidate who is tipped to be the party's first state leader in Germany, said it was a "historic victory" over the Christian Democrats, who had governed the state for 58 years.
Merkel's party and the Free Democrats (FDP), their junior partners in the state and at national level, claimed 44 per cent of the vote between them.
Guido Westerwelle, the FDP leader, said the vote was "a referendum on the future of atomic energy" as it was revealed 45 per cent of voters said nuclear power was a key election issue in light of the Japanese disaster.
"The dreadful events in Japan, the nuclear accident in Fukushima and the consequences for us in Germany: these were the most decisive topics in this state election," Westerwelle said.
Observers have said that losing Baden-Wuerttemberg, which lies on the French and Swiss borders and is home to car makers Daimler and Porsche, could weaken Merkel's grip on her party and make it even harder for her to pass legislation in the upper house of parliament.
However Christian Democrats leaders have stressed that the chancellor's position is safe.
The Baden-Wuerttemberg state election has been overshadowed by anger at Merkel's nuclear policy, as well as decisions on Libya and the euro.
Merkel had planned to extend the lifetime of Germany's nuclear reactors, four of which are based in Baden-Wuerttemberg, but the disaster in Japan prompted her to suspend this decision for three months.
She also temporarily shut off the seven oldest reactors pending a safety review.
Nick Spicer, Al Jazeera's correspondent in Stuttgart, said that the decision had not played well with voters, most of whom are opposed to nuclear power.
"People here didn't like it when she [Merkel] extended the life of those nuclear plants and then she announced, after the Japanese disaster, a re-think, of her policy," he said.
"But most people are seeing that as political opportunism, a ploy to distract voters from her policy, which the majority of Germans actually don't support."
In addition, conservative voters are critical of Berlin's abstention from a UN Security Council vote to create a no-fly zone in Libya, a break with Germany's Western allies.
German media has also been critical of Merkel for agreeing at an EU summit on Thursday to commit to a huge new rescue fund for struggling Eurozone economies.
Merkel's future could be clouded if the CDU loses. When Gerhard Schroeder, Merkel's SPD predecessor as chancellor, lost North Rhine-Westphalia in 2005, he called a snap election and lost.