The irony of the latest bit of bad news for Social Democrats is that the problem didn't even originate in their own party. On August 4, Elke Twesten, a member of the Greens in Lower Saxony's regional parliament, announced that she was leaving that party and joining the conservative CDU. Her defection eradicated the governing SPD-Green coalition's one-vote majority in the northern German state, traditionally a Social Democratic stronghold, making a snap election necessary.

The conservatives are leading the latest opinion poll in Lower Saxony, a large state that produced notable Social Democrats like former Chancellor Gerhard Schröder and German Foreign Minister Sigmar Gabriel. The SPD is facing the prospect of losing another of its major power bases after already having been defeated in three straight regional elections this year.

Social Democrats are crying foul, suggesting that the CDU actuvely encouraged Twesten to defect in an attempt to subvert the will of voters in the last regional election in 2014. Speaking in Berlin on Monday, SPD secretary general Hubertus Heil said that CDU had "questions to answer," such as whether the party had contact with Twesten before she announced her decision and whether any promises were made.

"Apparently she went over to the CDU because of personal ambitions and career frustration, not because of political beliefs," Heil said. "If they tried to lure her into a switch, that would put the CDU in a bad light indeed. They have to answer this question."

Heil, who is from Lower Saxony, added the conservatives were trying to "slink their way into power." But the CDU deny making any deal with Twesten, and more questions are being asked of the Social Democrats at the moment than of their opponents.

A campaign within a campaign

The national election campaign is entering its main phase. Volunteers are out on the streets hanging up posters, and SPD candidate for chancellor Martin Schulz is heading off to eastern Germany on Tuesday for the first leg of his summer tour. He'll try to erase a 15 point disadvantage to the conservatives in public opinion polls.

Heil would have loved to focus his message on Schulz's tour, but reporters kept asking about Lower Saxony. Not only is the government set to dissolve, but the still-governing state premier of Lower Saxony Stephan Weil is embroiled in controversy about letting carmaker Volkswagen vet a speech he made.

Heil said that the SPD stood behind Weil and would put him forward as its lead candidate in the local election. Heil said that controversy was part of a "campaign" on the part of CDU and said Weil had done nothing wrong.

"The allegations burst like a soap bubble," said Heil. "They have no basis in fact whatsoever."

Political potshots from the right

Here, too, the SPD have been unlucky. Because VW is partially owned by Lower Saxony, and the state premier sits on the company's supervisory board, regional leaders are per se open to allegations of colluding with the carmaker regardless of their party affiliation. But that didn't mean the CDU would let the opportunity pass to take a few political potshots.

In a parallel press conference, the conservatives' secretary general, Peter Tauber, said that Weil hadn't been able to "credibly refute" allegations that he acted on behalf of VW instead of in the interest of his constituents. He also sought to link the affair with the upcoming local election that is now needed.

"Lower Saxony urgently needs a new beginning, and Weil and his party shouldn't stand in the way," Tauber said, adding that the scandal and other failings had shown that the current regional government had "run its course."

New election on October 15

As the general secretaries of Germany's two biggest parties were trading barbs, party leaders in Lower Saxony were meeting in the capital, Hanover, to determine when the regional parliament would be dissolved and the snap election held. And to judge from the delays in the announcement, that meeting was hardly without disagreement.

There had been speculation that Lower Saxony could hold its election on September 24, the same day Germans go to the polls nationally. But on Monday afternoon, Weil said the regional vote would be held three weeks later.

"We have a situation that is - to put it mildly - not good for our state and that we wanted to end as quickly as possible with a new election," Weil said, adding that the date had been chosen after consulting with an election expert.

After the announcement, the CDU in Lower Saxony said that the election date was the earliest one possible. The party reiterated denials that it had encouraged Twesten to leave the Greens or had launched a campaign to bring down the state government.