The small state of Saarland is about to become a test tube for a new political alliance that could transform German politics. The Green Party has voted to form a government in the first three-way coalition with its former arch-rivals, the conservative CDU and the business-friendly FDP. It's a bold and risky move, say commentators.

Germany's Greens, now the smallest party in the federal parliament after scoring 10.7 percent in the Sept. 27 election, are accustomed to punching above their weight. As junior partner to the center-left Social Democrats in the federal government from 1998 to 2005, they made what had been a conservative industrial society more environmentally friendly and tolerant. They were the driving force behind the phasing out of nuclear power stations and an array of social reforms that included more liberal laws on same-sex partnerships.

Now they are spearheading an experiment in a small regional state that could eventually transform the nation's political landscape. Even though they won just 5.9 percent of the vote in an Aug. 30 regional election in the tiny south-western state of Saarland, with a population just over 1 million, the Greens have emerged as kingmakers in a new three-way alliance with former arch-rivals. They have also managed to wrest a string of policy concessions and are likely to get two cabinet posts in Saarland -- even though they only have three seats in the state assembly, out of a total of 51.

It will be Germany's first three-way coalition consisting of conservative Christian Democrats, pro-business Free Democrats and Greens. It's known as a "Jamaica" coalition because the parties' official colors of black, yellow and green match the colors of the Caribbean island's national flag.