And then there's the problem that the only people who have the possible power to pass electoral reform belong to one of the two major parties, and it's completely against the interest of those major parties to get rid of FPTP

This is generally true, but I’d say there’s a nonzero chance the Dems will be persuaded to support it – mostly because they’ve shown some support so far and because they don’t have a stranglehold on their base. The Republicans will fight it until their last breath, but the Dems are a coalition party held together by hopes and dreams, and they’ve been made to learn lately that they will lose if they don’t acknowledge progressives (this is part of why Walz was chosen – he’s the closest thing to a socialist they’ve chosen in recent memory). Without progressives, they will fail, and ditching FPTP would mean more engagement from a wide swathe of leftists, which would effectively shut out the far right. It’s in the best interest for the moderate left to be campaigning against the far left than the far right, and ditching FPTP would give them that.*.

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