The blurred lines between party figures, within the AfD's more radical faction, and "extremist" networks makes for a complex web of evolving groups and characters.

And it's a party that is constantly dealing with divisions about whether to adopt a more moderate or radical message.

"Remigration", for example, is an idea being embraced by some figures and kept at arm's length by others.

The concept is championed by Austrian activist Martin Sellner, who has a neo-Nazi past, and has been banned from both Germany and the UK.

He has written about "remigrating" asylum seekers, "foreigners" with residency rights and "non-assimilated" citizens.

Reports that senior AfD figures were involved in a "secret" meeting about remigration with Martin Sellner outside Berlin sparked mass demonstrations in Germany earlier this year.

The AfD is a movement that has, in the past decade, moved "more and more from a conservative, democratic party towards a right-wing extremist party," believes Stephan Kramer, the President of the Office for the Protection of the Constitution in Thuringia.

An outspoken civil servant, and a member of Chancellor Olaf Scholz's Social Democratic Party (SPD), Mr Kramer says the AfD's chances of winning the most seats in his own state this autumn are "very, very good".

Previously the general secretary of the Central Council of Jews in Germany, he says he would leave the country if the AfD won power.

The party's "nationalistic" views risk "turning Germany back into something that we've probably only seen between 1933 and 1945", he told the BBC.

AfD figures have argued that they are being targeted by state authorities that are biased against them, but Mr Kramer is adamant that is not the case: "We're not politicised because we're working on the basis of German law and any decision that is taken… can be challenged in front of a court."

A legal challenge by the AfD is ongoing - against its designation as "suspected" right-wing extremist, while its youth wing is classed as a confirmed case.