After getting trounced in the Iowa caucuses yesterday, Democratic Sens. Chris Dodd (Conn.) and Joe Biden (Del.) dropped out of the presidential race. Dodd was the only candidate who supported a corporate carbon tax as a means to fight climate change; both Dodd and Biden supported a cap-and-trade system to reduce greenhouse-gas emissions 80 percent below 1990 levels by 2050. If you’re feeling wistful about what might have been, read Grist’s environment-focused interviews with Dodd and Biden.

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