The Tory mayoral candidate for London, Susan Hall, was on Friday at the centre of a fresh race row.
Campaigners sent a compilation of tweets, likes and replies by Ms Hall to Tory HQ, calling for an investigation.
One of them was a Twitter/X like of a message quoting Enoch Powell, saying: “It’s never too late to save your country”.
The message, which includes a picture of Powell who is infamous for his “rivers of blood” speech, was posted by a Twitter user, dated February 16, 2020, stating: “It’s never too late to get London Back!”
Campaigners Hope Not Hate wrote to Greg Hands, the Conservative party chairman, calling for it to suspend Ms Hall and investigate.
The group’s director of campaigns, Georgie Laming, said: “Susan Hall is not fit to represent London and all its diversity.”
A source close to Ms Hall stressed that the exchange was a few months before the 2020 mayoral election was due to take place, before it was postponed, and that she had interpreted the tweet text (“it’s never too late to get London back”) as being about the upcoming election.
She was said not to be aware that the quote in the tweet graphic had been used by the BNP and would never endorse their views.
A spokesman for Hall’s campaign said “Susan engages with many people on Twitter without endorsing their views”.
A Tory spokesman said: “The Conservative party has an established code of conduct and formal processes where complaints can be made.”
Ms Hall, a London Assembly member and former Harrow council leader, last month attracted criticism for her tweets around Notting Hill Carnival, which led to critics accusing her of seeming “convinced of the innate criminality of Black people”.
Her campaign called that “desperate smears”.