Stop climate change, stop killing Palestinians, economic justice for working people
There are various strategies you could use for any of the three, with various levels of timeframe involved and chance of success and all, but "let Trump come to power" is not a real good solution to any of them, to me. "Stop supporting the Democrats until they suddenly decide to start supporting them" also seems weird to me and unlikely to succeed. People have been not caring about politics (with every righteous reason) for quite a while now, and it doesn't seem to have made the politics or the level of leftism progress in the equation any higher, to me.