It's not effective. At all.
It's alarmist claptrap. It goes right for the CNS and depletes any available emotional reactions after the 60th iteration. Nobody can sustain that level of panic-donating. Nobody.
I've got this idea.
It's something that ResistBot does and it works really well in my brain.
Why not- instead of filling email after email with alarmist bullshit, start sending region-targeted emails (based on zip codes) with daily or weekly lists of things- ACTUAL THINGS- that a local candidate intends to do, or actions one can take, or breakdowns of upcoming ballot measures. And start fucking including lesser elected positions too; school boards, municipal positions, sheriffs, judges. Concrete shit that is being done, or has been done, or soliciting feedback for projects or issues that need direct attention.
THEN, tag those communications with hard figures for what these actions cost. What the office staffing costs are. What the cost of the host server is each month. What it costs to pull permits for rallies, or send people out in the field to get petition signatures. And then- only then- do you make a donation request based on what THAT donation can do to offset those costs at THAT particular time.