Germany's Greens party, after years in opposition, has a shot of returning to power and promoting its leftist and pro-environment agenda as junior coalition partner to Chancellor Angela Merkel. The party that grew out of the 1960s and 70s pacifist and anti-nuclear movement previously governed as a junior ally of the Social Democrats from 1998 to 2005 and forms part of 10 state governments. Merkel, who won re-election with a weakened majority on Sunday, will need two partners to form the next government, allowing the Greens to flex their muscles as potential kingmakers.