By Sarah Marsh BERLIN (Reuters) -Polls opened on Sunday in the German state of Brandenburg, where the far-right Alternative for Germany (AfD) is projected to finish first, aiming to build on recent successes in other eastern states and surpass Chancellor Olaf Scholz's Social Democrats in this traditional stronghold.

Brandenburg is a longstanding stronghold for the party. But it is located in Germany’s relatively impoverished east, where the anti-immigrant A f D performs far better than in the west. That made this election a test of whether the SPD could beat the populists on its home ground.