Not surprising, given they were the only ones serious about advertising. We got so many leaflets from them at work and home and I even saw them on Reddit, yet nothing at all on those distribution channels from any other parties. I've seen some billboards by others, but it feels like 80% of the ones I've seen were SVP.
I personally hate them and didn't vote for them, but I don't think it's surprising they have such a big following.