Angela Merkel is about to discover if she can begin a fourth term as German chancellor or if she’s headed for another election.

With stable government in Europe’s biggest economy at stake, Germany’s Social Democratic Party plans to reveal on Sunday whether its members have voted to extend their coalition with Merkel through 2021. It’s the culmination of more than five months of party deadlock that have given Germany its longest bout of political uncertainty since World War II.

If the SPD ballot goes Merkel’s way, she could be sworn in by mid-March, returning to the European and global stage with full policy-making powers. A rejection would push Germany into untested waters, with Merkel expected to govern without a parliamentary majority and an early election likely in the fall.

While the impasse hasn’t noticeably dented Germany’s economic boom, Merkel’s European partners are growing anxious about the lack of political direction in Berlin as the U.K. negotiates its exit from the European Union and French President Emmanuel Macron seeks bold changes in the euro zone.

“We need Germany in the European debate,” Dutch Prime Minister Mark Rutte, a euro-area ally of Merkel’s, said during a visit to Berlin on Friday. “It will help enormously if there is a fully functioning government here in Germany.”

Hard to Call

Polls in the past two weeks suggest growing SPD support for the coalition pact that party leaders negotiated with Merkel’s Christian Democrat-led bloc last month. A Feb. 26-27 Infratest Dimap survey showed 66 percent of self-declared Social Democrat backers in favor.

Yet the mood among the party’s rank-and-file is hard to predict after the Social Democrats slumped to their worst postwar election result in September, triggering a youthful grass-roots movement to take the party into opposition.

SPD officials plan to start counting the mail-in ballots on Saturday and announce the result at about 9 a.m. Sunday in Berlin. The entire party membership of more than 460,000 was eligible to vote, marking the final hurdle in Merkel’s quest to extend her 12 years in office.

Reduced to acting chancellor for months, Merkel, 63, has said she intends to serve a full term until the next scheduled election in 2021 if the SPD stays on board.

German ‘Mess’

While a renewed “grand coalition” of the two biggest parties would signal Germany’s political center is holding, Merkel and her SPD allies face a polarized parliament that includes a far-right party for the first time since the 1950s as well as the anti-capitalist Left.

Germany’s expanded range of viable fringe options “has thrown everything into a mess,” Adam Posen, president of the Peterson Institute for International Economics, said on Bloomberg Television.