There's groups like Run for Something that recruit progressives to run for state and local office
A surprising number of potentially winnable seats are never contested. Let's show up anywhere and everywhere to fight back
If you're worried about Republicans messing with elections themselves, you also have the power to help there too by running for state and local offices. Elections - even for federal positions - are run by state and local officals not by the federal government
Given the low average salary of elected officials, this is really only an option for those who are already low income, independently wealthy, or in a dual income household (ideally if the other partner has decent income).
Unless it's not a full-time position. But most definitely money keeps people from getting involved