BERLIN (AP) — Germany's finance minister, a strong advocate of the Social Democrats' governing coalition with Chancellor Angela Merkel's conservatives, has won the first round of a membership ballot to lead the center-left party.

Olaf Scholz, who is also vice chancellor, and former regional lawmaker Klara Geywitz together received almost 22.7% of the vote in a race between six pairs.

Scholz and Geywitz face a party leadership runoff next month against lawmaker Saskia Esken and former regional minister Norbert Walter-Borjans, who received 21% support.

The Social Democrats, Germany's oldest party, are in a deep poll slump and agreed only reluctantly last year to continue as junior partners in a coalition with Merkel's bloc.

The party is expected to decide later this year whether to stay in Merkel's government or leave, possibly triggering an early election.