The far-right Alternative for Germany (AfD) party on Tuesday marked a 37% surge in party membership from last year.
In a statement, the AfD said its membership has climbed to 40,131, or a 37% rise from 2022.
The party got 10.3% of the vote in the 2021 general election, but in polls it has doubled its vote share since then, benefiting from broad dissatisfaction with the coalition government's policies.
According to recent surveys, the AfD is polling between 21% and 23%, making it the second-strongest political party in Germany after the conservative Christian Democratic Union (CDU).
It also made huge gains in October's regional elections to become the main opposition party in the federal states of Hesse and Bavaria.
Last month, an AfD candidate was elected mayor of the town of Pirna in the eastern state of Saxony, marking the first time that a candidate of the Islamophobic AfD was elected mayor of a German town.
