The Christian Democrats are blasted out of power that they have held since 1952.
remarkable victory over chancellor Angela Merkel's conservative party in a state election that had turned into a referendum on nuclear power in the wake of Japan's Fukushima disaster.
The Greens doubled their voter share in wealthy Baden-Wuerttemberg state and seemed poised to oust Merkel's Christian Democrats who held power there for almost six decades, according to preliminary results released by the state electoral commission.
The Greens are also set to win their first ever state governorship, the results showed. "This is a day that has strongly changed the political landscape in Germany," party chairwoman Claudia Roth said in Berlin.
The Greens secured 24.2 percent of the vote, with the center-left Social Democrats down 2 percentage points at 23.1 percent. That secures them a narrow lead to form a coalition government with a combined 71 seats in the state legislature, the results showed.
Christian Democrats secured 39 percent of the vote or 60 seats in the legislature. Its coalition partner, the pro-business Free Democrats, saw its voter share halved to 5.3 percent — 7 seats.
"We have secured what amounts to a historic electoral victory," the Greens' local leader Winfried Kretschmann told party members in Stuttgart.
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