and how does a sole candidate for mayor begin this 'grassroots campaign'. If you seriously start knocking on people's doors, you re most likely to end up dead or in prison in this day and age
Not in Europe, certainly not Denmark.
As a kid I've knocked on many doors selling lottery tickets for a charity. I think pretty much all streets in the town was assigned to a route and one or two people.
We still get people collecting from the red cross every year.
For the record I hated knocking on doors, if my kid ever comes home with lottery tickets to sell on a given route, I'll buy then all and burn them before his mom makes me sell any!
I'd honestly rather be a bad parent :)
More seriously, you can still hand out leaflets, meet with locals in public, cold-calling the locals, sticking placards, talking to journalists working for a local publication (if available).
I've lived in an apartment for a decade and I didn't know a single one of my neighbours. We all liked it that way.
What’s special about this? Are we in a period of particularly high migration? https://en.wikipedia.org/wiki/History_of_human_migration