Germany’s environmentalist Greens are gathering to put the finishing touches on their election pitch and to formally endorse Annalena Baerbock as their candidate for chancellor, amid a slip in their party's poll ratings fueled in large part by its own mistakes.

The Greens led many polls after Baerbock, 40, was nominated in April to make the party's first run for Germany's top public office. But more recent surveys show outgoing Chancellor Angela Merkel's center-right Union bloc overtaking the Greens, and a state election last weekend brought a big conservative win and a disappointing Green showing.

The party still has plenty of reasons to fight ahead of Germany's Sept. 26 national election. The Greens are still polling 20% or more — more than twice the 8.9% of the vote the party received in Germany's last election, in 2017. With Merkel stepping down after 16 years in power, no candidate has the advantage of incumbency.

Germany's Green party co-leaders Robert Habeck, right, and Annalena Baerbock, left, react as they visit the venue where the party's online Congress will take place tomorrow, in Berlin, Germany, Thursday, June 10, 2021. (John MacDougallPool via AP)

Germany's Green party co-leaders Robert Habeck, right, and Annalena Baerbock, left, react as they visit the venue where the party's online Congress will take place tomorrow, in Berlin, Germany, Thursday, June 10, 2021. (John MacDougallPool via AP)

Still, a prominent lawmaker and former party leader cautioned members against forcing radical changes to the Greens' draft election platform during a three-day online congress that opens Friday. The platform foresees speeding up Germany's exit from coal-fired power, raising carbon prices and massively increasing infrastructure spending.

Some members want more: for example, to toughen a pledge to introduce a 130 kph (81 mph) speed limit on Germany’s autobahn highways, many stretches of which lack any limits, and to instead make it 100 kph (62 mph).

Ex-leader Cem Ozdemir told the Rheinische Post newspaper that the more moderate promise is what most Germans want and “there is no climate protection against the majority.”

Germany's Green Party co-chairwoman, Annalena Baerbock, a candidate for Chancellor, gives an interview before her party's federal delegates' conference, in Berlin, Germany, Thursday, June 10, 2021. At the party conference, the election programme for the Bundestag elections is adopted. (Kay Nietfelddpa via AP)

Germany's Green Party co-chairwoman, Annalena Baerbock, a candidate for Chancellor, gives an interview before her party's federal delegates' conference, in Berlin, Germany, Thursday, June 10, 2021. At the party conference, the election programme for the Bundestag elections is adopted. (Kay Nietfelddpa via AP)

The Greens have taken heat from opponents lately over a poorly presented plan to raise gasoline prices and talk of ending short-haul flights — which they don't actually aim to ban — and after some entries in a compact version of Baerbock's resume had to be corrected.

“I obviously made a mistake there,” Baerbock told ARD television on Thursday. “And I am very, very sorry about that.”

Ozdemir was relatively relaxed about recent events. “It's better that we make mistakes that can be corrected now than shortly before the election,” he said.