BERLIN (BLOOMBERG) - Bavarian Premier Markus Soeder conceded that the conservative alliance may fail to hit a goal of comfortably winning next month's election as a poll put the Social Democrats (SPD) in the lead for the first time.

The Forsa survey showed SPD support climbing to 23 per cent, inching ahead of Chancellor Angela Merkel's CDU/CSU bloc, which is on 22 per cent, down from more than 30 per cent as recently as March.

The SPD hasn't led in that poll since October 2006, and it suggests Dr Merkel's alliance may be in danger of losing its grip on power for the first time since she won her debut election in 2005.

Dr Merkel, who is stepping down as chancellor, tried to downplay the poll, and said the bloc will keep fighting for support ahead of the Sept 26 vote.

"We will work every day for a good result, and we are not looking at polls every day," she said on Tuesday (Aug 24).

Mr Soeder, who heads a key faction in the bloc, said that the campaign would be a "head-to-head" race right up until polling day.

"I admit that a few weeks ago, I would have had higher goals," Mr Soeder, leader of the Bavaria-based Christian Social Union (CSU), said in a Bloomberg webinar. "That's becoming more and more difficult - and, one has to admit, not entirely realistic."

The election will now be about who will succeed Dr Merkel to lead a new government, Mr Soeder said. He lost an internal contest to become chancellery candidate to Mr Armin Laschet, whose gaffe-prone campaign so far has failed to convince voters.

With Greens candidate Annalena Baerbock also on the defensive after mistakes in her campaign, Mr Olaf Scholz, Dr Merkel's low-key SPD finance minister, has enjoyed a surge in momentum.

That's prompted Mr Soeder, 54, to go on the attack, offering a taste of the tactics the Christian Democratic Union (CDU) and its CSU sister party will deploy on the campaign trail.

He raised the spectre of an SPD-led government that would impose "brutal indebtedness", abandon balanced budgets and back "massive" tax hikes.

In fact, the Social Democrats have called for a looser fiscal policy and new taxes on the rich, including a wealth tax, though they support tax relief for the less wealthy.

The SPD has stopped short of calling for changes to Germany's constitutional debt brake, which imposes limits on borrowing.

"I think we can remain number one," Mr Soeder said, adding that current polls don't yet reflect the bloc's full campaign effort.

The Social Democrats were briefly ahead of Dr Merkel's bloc in some polls in early 2017, but Dr Merkel went on to win the election later that year by more than 10 points, securing a fourth term.

The party that wins the most support will have the opportunity to form a ruling coalition, which is getting increasingly complex. The most likely outcome is a three-way alliance, with either the SPD or the conservative bloc at the helm.

The Greens and the pro-business Free Democrats could also play a role.

The Forsa poll had the Greens at 18 per cent, down a point, and the Free Democrats at 12 per cent.

That would put both the SPD and the CDU in position to lead a three-way coalition with the Greens and FDP.

The Aug 17-23 survey polled 2,504 people and has a margin of error of +/- 2.5 per cent.

Full backing

Although he lost his challenge to lead the conservatives, Mr Soeder expressed his full backing for Mr Laschet despite the CDU candidate struggling to convince voters of his leadership potential.

After a messy nomination battle, Mr Laschet - the 60-year-old state premier of North Rhine-Westphalia - has committed a series of blunders on the campaign trail. This included laughing in the midst of flood wreckage.

That has opened the field to Mr Scholz, a former Hamburg mayor and trained labour lawyer. The 63-year-old has played up his experience helping protect jobs and businesses from the fallout of the coronavirus, and his low-key pragmatism has similarities to Dr Merkel, who remains Germany's most popular politician.