We dominate fly over country. Secession in all but name.

Start local; for every position in governance, no matter how small, a patriot. Build communities so that they become self-contained and self-sufficient.

Grow until our influence allows us to declare ourselves as de facto "freedom sanctuaries". Operate at nothing greater than the state level.

Others seeking freedom will follow. The unwelcome i.e. the Leftists will continue to dominate urban centers, where their influence will be contained.

DC becomes the head of a vestigial governance, only truly holding sway on the coasts, unable to enact rule over the populist collective.

This will take decades, but it's achievable.