According to polls[0] the party gets ~20% votes in their region. IMHO 20% of voters can't be "extreme"
[0] https://www.svt.se/nyheter/lokalt/orebro/orebropartiet-nast-... (swedish)
Was the NSDAP "extreme"? They got 43.9%
Their ideology implied at the very least getting rid of whole populations. They wanted to reset to an imagined ancient culture and rewrote history to justify it. Mostly imagined, anyway - Sparta was the one real example they looked to.