Germany’s troubled Social Democrats (SPD) on Monday discussed appointing three caretaker leaders after Andrea Nahles quit, with members appalled by plummeting popularity agitating for the party to leave Chancellor Angela Merkel’s scrappy coalition.

Nahles, the most vocal backer of the SPD’s reluctant decision to form a third so-called “grand coalition” with Merkel’s conservatives, formally quit on Monday after a disastrous showing at last weekend’s European elections.

Voters have punished the SPD for its decision to step in as a coalition partner of last resort with ever more disastrous poll showings, culminating last weekend in the party being toppled in its stronghold city of Bremen after 70 years.

SPD sources said party chiefs proposed three caretakers to jointly lead the party while it takes time to settle on a new leader: Manuela Schwesig and Malu Dreyer, the premiers of the states of Mecklenburg-Vorpommern and Rhineland-Palatinate respectively, and Thorsten Schaefer-Guembel, who leads the SPD in Hesse.

“I believe a coalition walk-out has to come,” said Simone Lange, mayor of the northern town of Flensburg, who challenged Nahles for the party leadership at the contest last year.

“The question is when is the right time to do it.”

The ruling coalition is due to run until 2021 but a midterm review in the autumn could be an opportunity for the SPD to pull the plug on the alliance.

The options facing the SPD are unappealing.

Early elections would likely decimate the party, running third in the polls behind the surging Greens. But the SPD is struggling to appeal to its traditional working-class voter base while its leaders share power with Merkel’s conservatives.

“It is hard to see why the SPD would want to trade its chunk of governmental power for the impotence of an opposition role. But the party is rudderless and deeply wounded,” said Josef Joffe, publisher-editor of weekly Die Zeit.

“In these straits, wild dreams have wings, and so the clamour for rebirth in opposition may end its unhappy marriage with Merkel,” he added.

Finance Minister Olaf Scholz, the SPD’s most popular politician, told ARD television he would not have time to combine that job with leading the party.

Merkel said on Sunday her conservatives were committed to seeing through the grand coalition: “We will continue the government work with all sincerity and a great sense of responsibility,” she said.

If the SPD decides to pull out of the ruling alliance, options include new elections, an even more unwieldy coalition of three party groups, or a minority conservative government propped up on an ad hoc basis.

The price of any of these options would likely be an end to Merkel’s almost 14-year-old tenure as chancellor.

The ecologist Greens would play a key role in the arithmetic of a new coalition after they surged past the SPD in last week’s European elections and came first, ahead of Merkel’s conservatives, in an opinion poll released on Saturday.

Annalena Baerbock, co-leader of the ecologist Greens, told broadcaster ZDF her party could not be relied on as “reserves who can simply jump in if the government runs out of strength.”

Should the grand coalition falter, she wanted new elections:

“Then society, then the citizens of this country need to decide again because the personnel, the issues are all different than two and a half years ago after the last federal election. That means, then there need to be new elections,” Baerbock said.