Indivisible and some others are working on a mail campaign...
get everyone you know to write 20 letters, and they get everyone they know to write 20 letters...
You know how that works, and how chain letters eventually kinda wind down. They can help, though. And the personal touch often beats email.
Howsumever, the Post Office once had a deal where you would upload your graphic and message and they would send everyone in your zip code a postcard. Or half the people. Or less. As many as you can afford.
It's still done, although it's outsourced now, and a lot of the junk mail you get is through this method. (They will also print letters and stuff envelopes for you) A properly designed post card might actually be read, or stuck on the fridge.
So, I'm working with our local committees to come up with some messages to get out there, and the money to get them out there. Some local print shops can do this sort of thing, too, and the trick is to get the price down while getting all the drudge work outsourced. No sheets of addresses or stamps to stick on there.
Lists by party exist at your board of elections, and messages can be aimed at Democrats, other sympathetic parties, unknowns and even Republicans and Conservatives.