The SPD had 26% of the vote, according to the exit poll, with the center-right Christian Democratic Union of outgoing Chancellor Angela Merkel on 24%, followed by the Greens at 14.5%, the FDP at 12% and the AfD at 10%.
The narrowness of the margins means the German elections are at this point too close to call and predicting the next government — and chancellor — is impossible.
The leader of the SPD, Olaf Scholz, has been seen as one of the leading candidates for the role, as has the CDU’s Armin Laschet.
The reaction at the CDU headquarters as the initial exit polls emerged was one of disappointment, however, with the numbers suggesting it could be looking at the worst result in the party’s history.
“This is a result with bitter losses — there’s no way to sugarcoat it,” said CDU secretary-general Paul Zemiak. “This result really hurts.”
But, Zemiak added, the results are not yet final. “The evening is long and we will see what the next few hours will bring,” he said.
The crowd at the Green party headquarters in Berlin cheered as the first exit polls were being read out.