Back in 2019, Lake Research Partners conducted a housing study for California YIMBY. One of the questions that California voters were asked was about whether or not they support or oppose having more housing built in their community. Here is how people responded (about 700 interviews were conducted by phone and about 500 people were asked online):
What this seems to suggest is that most people (61% of all voters) support more housing in their community, with 38% (the darker bar) feeling very strongly about it. These results also seem to suggest that if you're already a homeowner and/or if you're a Republican, that you are then less likely to support housing in your community (51% and 54%, respectively). Even still, one possible conclusion that you can draw from these findings is that, perhaps in all cases, a majority of people (>50%) support the idea of more housing in their community.
However, the problem with this approach is that you're ultimately asking a pretty generic and theoretical question about housing supply. I am presuming that this is a scenario where the rubber has not yet hit the road. Indeed, most people will say that they support new housing in their backyard, but is that actually how things will play it? It's pretty common, for example, to hear things like: "I support new development, but I think this project is simply too ___________."
So while I think that there are some interesting directional indicators that one could draw from these findings, I suspect that the numbers in the real world might be slightly less rosy.
